Door number 24 ...
It is the smallest number with exactly eight divisors: 1, 2, 3, 4, 6, 8, 12, and 24.
24 is a Harshad and semi-meandric number.
Twentyfour is the atomic number of chromium. Also the number of hours in an earth day. Its the number of books in the Tanakh. In Christian apocalyptic literature it represents the complete Church, being the sum of the 12 tribes of Israel and the 12 Apostles of the Lamb of God.
There are 24 major and minor keys in Western tonal music, not counting enharmonic equivalents. Therefore, for collections of pieces written in each key, the number of pieces in such a collection; e.g., Chopin's 24 Preludes.
Twenty four teams that participated in each FIFA World Cup finals tournament between 1982 and 1994. Also the number of teams that will participate in the finals of the FIFA Women's World Cup starting in 2015.
24 is the number of bits a computer needs to represent TrueColor images (for a maximum of 16,777,216 colours). (But greater numbers of bits provide more accurate colors. "TrueColor" is one of many possible representations of colors.)
24 is an American television series produced for the Fox network and syndicated worldwide, starring Kiefer Sutherland as Counter Terrorist Unit (CTU) agent Jack Bauer. Each 24-episode season covers 24 hours in the life of Bauer, using the real time method of narration. Premiering on November 6, 2001, the show spanned 192 episodes over eight seasons, with the series finale broadcast on May 24, 2010. In addition, the television movie 24: Redemption was broadcast between seasons six and seven, while a feature film of the same name is also planned.
A track from one of my favourite bandsand probably one of the most exciting I have ever seen live.