What's your favourite number number? The top ten best number songs

Lots of songs have numbers in their titles: from 5-4-3-2-1 to 99 Luftballons. But what makes a great "number song"? Music journalist and self-appointed rock numerologist David Klein has spent years researching this very question for his new book If 6 was 9. Here he lists his all time top ten.

10. "One" - Nilsson (1968)