Fait général: 2809 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 2809 is an unremarkable number.
Culture générale: 2809 is an uninteresting number.
Date historique: September 9th is the day in 1379 that Treaty of Neuberg, splitting the Austrian Habsburg lands between the Habsburg Dukes Albert III and Leopold III.