Fait mathématique: 1626 is the number of binary partitions of 31.
Culture générale: 1626 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Date historique: June 13th is the day in 1525 that Martin Luther marries Katharina von Bora, against the celibacy rule decreed by the Roman Catholic Church for priests and nuns.