Fait mathématique: 4443 is a number n for which n^{2}+1 is 10 times another square.
Culture générale: 4443 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Date historique: February 29th is the day in 1956 that U.S. President Dwight D. Eisenhower announces to the nation that he is running for a second term.