Please read the following table in HTML format from a webpage and then answer the question in detail according to the table. Each table cell is defined by a <td> and a </td> tag. Each table row starts with a <tr> and ends with a </tr> tag. 'rowspan=m' and 'colspan=n' represents a cell spaning over 'm' rows and 'n' columns.

Webpage title:
Sierpc County
Table title:
Administrative division
Table:
<table id='hittask' contenteditable='False'>
<tr> <td colspan=1 rowspan=1 > Gmina </td><td colspan=1 rowspan=1 > Type </td><td colspan=1 rowspan=1 > Area (km²) </td><td colspan=1 rowspan=1 > Population (2006) </td><td colspan=1 rowspan=1 > Seat </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > Sierpc </td><td colspan=1 rowspan=1 > urban </td><td colspan=1 rowspan=1 > 18.6 </td><td class="highlighted"  colspan=1 rowspan=1 > 18,791 </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > Gmina Sierpc </td><td class="highlighted"  colspan=1 rowspan=1 > rural </td><td colspan=1 rowspan=1 > 150.2 </td><td class="highlighted"  colspan=1 rowspan=1 > 7,141 </td><td colspan=1 rowspan=1 > Sierpc * </td></tr>
<tr> <td colspan=1 rowspan=1 > Gmina Zawidz </td><td class="highlighted"  colspan=1 rowspan=1 > rural </td><td colspan=1 rowspan=1 > 186.1 </td><td class="highlighted"  colspan=1 rowspan=1 > 6,956 </td><td colspan=1 rowspan=1 > Zawidz </td></tr>
<tr> <td colspan=1 rowspan=1 > Gmina Mochowo </td><td class="highlighted"  colspan=1 rowspan=1 > rural </td><td colspan=1 rowspan=1 > 143.6 </td><td class="highlighted"  colspan=1 rowspan=1 > 6,249 </td><td colspan=1 rowspan=1 > Mochowo </td></tr>
<tr> <td colspan=1 rowspan=1 > Gmina Gozdowo </td><td class="highlighted"  colspan=1 rowspan=1 > rural </td><td colspan=1 rowspan=1 > 126.7 </td><td class="highlighted"  colspan=1 rowspan=1 > 6,041 </td><td colspan=1 rowspan=1 > Gozdowo </td></tr>
<tr> <td colspan=1 rowspan=1 > Gmina Szczutowo </td><td class="highlighted"  colspan=1 rowspan=1 > rural </td><td colspan=1 rowspan=1 > 112.6 </td><td class="highlighted"  colspan=1 rowspan=1 > 4,417 </td><td colspan=1 rowspan=1 > Szczutowo </td></tr>
<tr> <td colspan=1 rowspan=1 > Gmina Rościszewo </td><td class="highlighted"  colspan=1 rowspan=1 > rural </td><td colspan=1 rowspan=1 > 115.1 </td><td class="highlighted"  colspan=1 rowspan=1 > 4,216 </td><td colspan=1 rowspan=1 > Rościszewo </td></tr>
<tr> <td colspan=5 rowspan=1 > * seat not part of the gmina </td></tr>
</table>
Question:
What is the composition of Sierpc county as of 2006?
Answer:
As of 2006, Sierpc County's total population was 53,811, out of which the population of Sierpc was 18,791 and the rural population was 35,020.