Fait général: 2560 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 2560 is the number of 2×2 singular matrices mod 8.
Culture générale: 2560 is an uninteresting number.
Date historique: January 3rd is the day in 1777 that American general George Washington defeats British general Charles Cornwallis at the Battle of Princeton.