Fait mathématique: 4155 is 4^{5} + 1^{5} + 5^{5} + 5.
Culture générale: 4155 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Date historique: May 17th is the day in 1943 that the United States Army contracts with the University of Pennsylvania's Moore School to develop the ENIAC.