Fait général: 5611 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 5611 is the smallest number for which it and the 3 numbers before and after it all have f(n) divisible by 10.
Culture générale: 5611 is an unremarkable number.
Date historique: May 12th is the day in 1191 that Richard I of England marries Berengaria of Navarre who is crowned Queen consort of England the same day.