Fatto generale: 52 is the number of white keys (notes in the C major scale).
Fatto matematico: 52 is the 5^{th} Bell number.
Trivia: 52 is the number of white keys (notes in the C major scale).
Data storica: February 21st is the day in 1952 that the British government, under Winston Churchill, abolishes identity cards in the UK to "set the people free".