Fait général: 21590 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 21590 is a boring number.
Culture générale: 21590 is an uninteresting number.
Date historique: February 9th is the day in 1996 that the Provisional Irish Republican Army declares the end to its 18 month ceasefire and explodes a large bomb in London's Canary Wharf.