Fait général: 15971 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 15971 is an uninteresting number.
Culture générale: 15971 is an unremarkable number.
Date historique: September 22nd is the day in 1236 that the Lithuanians and Semigallians defeat the Livonian Brothers of the Sword in the Battle of Saule.