The following table sets forth the number of net customer additions (losses):
## Table 0 ##
Net customer additions were 8,334,000 in 2014, compared to net customer additions of 4,377,000 in 2013.
At December 31, 2014, we had 55.0 million customers, an 18% increase from the customer total as of December 31, 2013, as a result of growth in all customer categories, as described below.
Net customer additions, excluding customers acquired as a result of the MetroPCS business combination were 4,377,000 in 2013, compared to 203,000 net customer additions in 2012.
At December 31, 2013, we had 46.7 million customers, a 40% increase from the customer total as of December 31, 2012.
The increase was primarily driven by the addition of MetroPCS’s customer base due to the completion of the business combination during the second quarter of 2013, which increased the branded prepaid customer base by 8,918,000.
Branded Customers Branded postpaid phone net customer additions were 4,047,000 in 2014, compared to branded postpaid phone net customer additions of 1,938,000 in 2013.
The increase in customer development was attributable to increased new customer activations and improved branded postpaid phone churn driven by the continued success of our Un-carrier proposition and strong customer response to promotions for services and devices.
Additional increases in customer development resulted from the launch of new popular devices.
Branded postpaid phone net customer additions were 1,938,000 in 2013, compared to branded postpaid phone net customer losses of 2,092,000 in 2012.
The significant improvement in customer development was primarily attributable to improved branded postpaid phone churn, increased new customer activations and qualified upgrades of branded prepaid customers to branded postpaid plans.
Branded postpaid phone net customer additions benefited from the launch of Simple Choice plans as a component of the Un-carrier proposition and launch of popular devices in 2013.
These factors drove incremental gross additions for branded postpaid phone customers and improved churn as further described below.
Branded postpaid mobile broadband net customer additions were 839,000 in 2014, compared to branded postpaid mobile broadband net customer additions of 68,000 in 2013.
The significant increase was driven by strong customer response to promotions for mobile broadband services and devices.
Branded postpaid mobile broadband net customer additions were 68,000 in 2013, compared to branded postpaid mobile broadband net customer additions of 18,000 in 2012.
The increase was driven by the positive customer response to the “Tablets Un-leashed” promotion launched in October 2013.
Branded prepaid net customer additions were 1,244,000 in 2014, compared to branded prepaid net customer additions of 328,000 in 2013.
The increase in customer development was attributable to higher branded prepaid gross customer additions due to the growth and expansion of the MetroPCS brand, including the launch into additional markets following the MetroPCS business combination in April 2013.
This increase was offset in part by higher deactivations from the competitive environment in the prepaid market.
Branded prepaid net customer additions, excluding customers of MetroPCS acquired as a result of the business combination, were 328,000 in 2013, compared to 1,007,000 branded prepaid net customer additions in 2012.
The decrease was partly a result of qualified upgrades of branded prepaid customers to branded postpaid plans as the Un-carrier proposition eliminates
Our previously announced stock repurchase program, and any subsequent stock purchase program put in place from time to time, could affect the price of our common stock, increase the volatility of our common stock and could diminish our cash reserves.
Such repurchase program may be suspended or terminated at any time, which may result in a decrease in the trading price of our common stock.
We may have in place from time to time, a stock repurchase program.
Any such stock repurchase program adopted will not obligate the Company to repurchase any dollar amount or number of shares of common stock and may be suspended or discontinued at any time, which could cause the market price of our common stock to decline.
The timing and actual number of shares repurchased under any such stock repurchase program depends on a variety of factors including the timing of open trading windows, the price of our common stock, corporate and regulatory requirements and other market conditions.
We may effect repurchases under any stock repurchase program from time to time in the open market, in privately negotiated transactions or otherwise, including accelerated stock repurchase arrangements.
Repurchases pursuant to any such stock repurchase program could affect our stock price and increase its volatility.
The existence of a stock repurchase program could also cause our stock price to be higher than it would be in the absence of such a program and could potentially reduce the market liquidity for our stock.
There can be no assurance that any stock repurchases will enhance stockholder value because the market price of our common stock may decline below the levels at which we repurchased shares of common stock.
Although our stock repurchase program is intended to enhance stockholder value, short-term stock price fluctuations could reduce the program’s effectiveness.
Additionally, our share repurchase program could diminish our cash reserves, which may impact our ability to finance future growth and to pursue possible future strategic opportunities and acquisitions.
See Item 5.
Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities and Note 10 - Repurchases of Common Stock included in Part II of this Form 10-K for further information.
Item 1B.
Unresolved Staff Comments None.
Item 2.
Properties As of December 31, 2017, our significant properties that we primarily leased and were used in connection with switching centers, data centers, call centers and warehouses were as follows:
## Table 1 ##
As of December 31, 2017, we primarily leased: ?
Approximately 61,000 macro sites and approximately 18,000 distributed antenna system and small cell sites.  ?
Approximately 2,200 T-Mobile and MetroPCS retail locations, including stores and kiosks ranging in size from approximately 100 square feet to 17,000 square feet.  ?
Office space totaling approximately 900,000 square feet for our corporate headquarters in Bellevue, Washington.
We use these offices for engineering and administrative purposes.  ?
Office space throughout the U. S. , totaling approximately 1,700,000 square feet as of December 31, 2017, for use by our regional offices primarily for administrative, engineering and sales purposes.
In February 2018, we extended the leases related to our corporate headquarters facility.
Item 3.
Legal Proceedings See Note 13 - Commitments and Contingencies of the Notes to the Consolidated Financial Statements included in Part II, Item 8 of this Form 10-K for information regarding certain legal proceedings in which we are involved.
Branded prepaid ARPU increased $0.24, or 1%, in 2016 primarily from: ?
A decrease in certain customers that had lower average branded prepaid ARPU, as well as higher data attach rates; partially offset by ?
Dilution from growth of customers on rate plan promotions.
Adjusted EBITDA Adjusted EBITDA represents earnings before Interest expense, net of Interest income, Income tax expense, Depreciation and amortization, non-cash Stock-based compensation and certain income and expenses not reflective of T-Mobile’s operating performance.
Net income margin represents Net income divided by Service revenues.
Adjusted EBITDA margin represents Adjusted EBITDA divided by Service revenues.
Adjusted EBITDA is a non-GAAP financial measure utilized by our management to monitor the financial performance of our operations.
We use Adjusted EBITDA internally as a metric to evaluate and compensate our personnel and management for their performance, and as a benchmark to evaluate our operating performance in comparison to our competitors.
Management believes analysts and investors use Adjusted EBITDA as a supplemental measure to evaluate overall operating performance and facilitate comparisons with other wireless communications companies because it is indicative of our ongoing operating performance and trends by excluding the impact of interest expense from financing, non-cash depreciation and amortization from capital investments, non-cash stock-based compensation, network decommissioning costs as they are not indicative of our ongoing operating performance and certain other nonrecurring income and expenses.
Adjusted EBITDA has limitations as an analytical tool and should not be considered in isolation or as a substitute for income from operations, net income or any other measure of financial performance reported in accordance with U. S.  Generally Accepted Accounting Principles (“GAAP”).
The following table illustrates the calculation of Adjusted EBITDA and reconciles Adjusted EBITDA to Net income, which we consider to be the most directly comparable GAAP financial measure:
## Table 2 ##
(1) The amortized imputed discount on EIP receivables previously recognized as Interest income has been retrospectively re-classified as Other revenues.
See the table below and Note 1 - Summary of Significant Accounting Policies of the Notes to the Consolidated Financial Statements included in Part II, Item 8 of this Form 10-K for further information.
(2) Beginning in the first quarter of 2017, the Company will no longer separately present Cost of MetroPCS business combination as it is insignificant.
(3) Stock-based compensation includes payroll tax impacts and may not agree to stock-based compensation expense in the consolidated financial statements.
(4) Other, net may not agree to the Consolidated Statements of Comprehensive Income primarily due to certain non-routine operating activities, such as other special items that would not be expected to reoccur, and are therefore excluded in Adjusted EBITDA.
Cash Flows The following is an analysis of our cash flows for the years ended December 31, 2017, 2016 and 2015:

<table><tr><td></td><td colspan="3">Year Ended December 31,</td></tr><tr><td>(in thousands)</td><td>2014</td><td>2013</td><td>2012</td></tr><tr><td>Net customer additions (losses)</td><td></td><td></td><td></td></tr><tr><td>Branded postpaid phone customers</td><td>4,047</td><td>1,938</td><td>-2,092</td></tr><tr><td>Branded postpaid mobile broadband customers</td><td>839</td><td>68</td><td>18</td></tr><tr><td>Total branded postpaid customers</td><td>4,886</td><td>2,006</td><td>-2,074</td></tr><tr><td>Branded prepaid customers</td><td>1,244</td><td>328</td><td>1,007</td></tr><tr><td>Total branded customers</td><td>6,130</td><td>2,334</td><td>-1,067</td></tr><tr><td>M2M customers</td><td>819</td><td>512</td><td>660</td></tr><tr><td>MVNO customers</td><td>1,385</td><td>1,531</td><td>610</td></tr><tr><td>Total wholesale customers</td><td>2,204</td><td>2,043</td><td>1,270</td></tr><tr><td>Total net customer additions</td><td>8,334</td><td>4,377</td><td>203</td></tr><tr><td>Acquired customers</td><td>—</td><td>8,918</td><td>—</td></tr></table>
<table><tr><td></td><td>Approximate Number</td><td>Approximate Size in Square Feet</td></tr><tr><td>Switching centers</td><td>61</td><td>1,300,000</td></tr><tr><td>Data centers</td><td>6</td><td>500,000</td></tr><tr><td>Call center</td><td>17</td><td>1,400,000</td></tr><tr><td>Warehouses</td><td>15</td><td>500,000</td></tr></table>
<table><tr><td></td><td colspan="3">Year Ended December 31,</td><td colspan="2">2017 Versus 2016</td><td colspan="2">2016 Versus 2015</td></tr><tr><td>(in millions)</td><td>2017</td><td>2016</td><td>2015</td><td>$ Change</td><td>% Change</td><td>$ Change</td><td>% Change</td></tr><tr><td>Net income</td><td>$4,536</td><td>$1,460</td><td>$733</td><td>$3,076</td><td>211%</td><td>$727</td><td>99%</td></tr><tr><td>Adjustments:</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Interest expense</td><td>1,111</td><td>1,418</td><td>1,085</td><td>-307</td><td>-22%</td><td>333</td><td>31%</td></tr><tr><td>Interest expense to affiliates</td><td>560</td><td>312</td><td>411</td><td>248</td><td>79%</td><td>-99</td><td>-24%</td></tr><tr><td>Interest income<sup>-1</sup></td><td>-17</td><td>-13</td><td>-6</td><td>-4</td><td>31%</td><td>-7</td><td>117%</td></tr><tr><td>Other (income) expense, net</td><td>73</td><td>6</td><td>11</td><td>67</td><td>1,117%</td><td>-5</td><td>-45%</td></tr><tr><td>Income tax expense (benefit)</td><td>-1,375</td><td>867</td><td>245</td><td>-2,242</td><td>-259%</td><td>622</td><td>254%</td></tr><tr><td>Operating income<sup>-1</sup></td><td>4,888</td><td>4,050</td><td>2,479</td><td>838</td><td>21%</td><td>1,571</td><td>63%</td></tr><tr><td>Depreciation and amortization</td><td>5,984</td><td>6,243</td><td>4,688</td><td>-259</td><td>-4%</td><td>1,555</td><td>33%</td></tr><tr><td>Cost of MetroPCS business combination<sup>-2</sup></td><td>—</td><td>104</td><td>376</td><td>-104</td><td>-100%</td><td>-272</td><td>-72%</td></tr><tr><td>Stock-based compensation<sup>-3</sup></td><td>307</td><td>235</td><td>222</td><td>72</td><td>31%</td><td>13</td><td>6%</td></tr><tr><td>Other, net<sup>-4</sup></td><td>34</td><td>7</td><td>42</td><td>27</td><td>386%</td><td>-35</td><td>-83%</td></tr><tr><td>Adjusted EBITDA<sup>-1</sup></td><td>$11,213</td><td>$10,639</td><td>$7,807</td><td>$574</td><td>5%</td><td>$2,832</td><td>36%</td></tr><tr><td>Net income margin (Net income divided by service revenues)</td><td>15%</td><td>5%</td><td>3%</td><td></td><td>1000 bps</td><td></td><td>200 bps</td></tr><tr><td>Adjusted EBITDA margin (Adjusted EBITDA divided by service revenues)<sup>(1)</sup></td><td>37%</td><td>38%</td><td>31%</td><td></td><td>-100 bps</td><td></td><td>700 bps</td></tr></table>

Question: What is the total amount of Branded postpaid phone customers of Year Ended December 31, 2014, and Warehouses of Approximate Size in Square Feet ?
Answer: 504047