Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Tie no | Home team | Score | Away team | Date |
| --- | --- | --- | --- | --- |
| 1 | Blackpool | 2–1 | Stockport County | 27 January 1951 |
| 2 | Bristol City | 1–0 | Brighton & Hove Albion | 27 January 1951 |
| 3 | Preston North End | 0–2 | Huddersfield Town | 27 January 1951 |
| 4 | Wolverhampton Wanderers | 3–1 | Aston Villa | 27 January 1951 |
| 5 | Sunderland | 2–0 | Southampton | 27 January 1951 |
| 6 | Derby County | 1–3 | Birmingham City | 27 January 1951 |
| 7 | Luton Town | 1–2 | Bristol Rovers | 27 January 1951 |
| 8 | Sheffield United | 0–0 | Mansfield Town | 27 January 1951 |
| Replay | Mansfield Town | 4–2 | Sheffield United | 31 January 1951 |
| 9 | Newcastle United | 3–2 | Bolton Wanderers | 27 January 1951 |
| 10 | Manchester United | 4–0 | Leeds United | 27 January 1951 |
| 11 | Millwall | 0–1 | Fulham | 27 January 1951 |
| 12 | Hull City | 2–0 | Rotherham United | 27 January 1951 |
| 13 | Exeter City | 1–1 | Chelsea | 27 January 1951 |
| Replay | Chelsea | 2–0 | Exeter City | 31 January 1951 |
| 14 | Newport County | 0–2 | Norwich City | 27 January 1951 |
| 15 | Arsenal | 3–2 | Northampton Town | 27 January 1951 |
| 16 | Stoke City | 1–0 | West Ham United | 27 January 1951 |
Question:
What is the date when tie number is 6?
Answer:
27 January 1951