Fatto generale: 2680 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 2680 is the number of different arrangements of 11 non-attacking queens on an 11×11 chessboard.
Trivia: 2680 is an unremarkable number.
Data storica: May 3rd is the day in 1791 that the Constitution of May 3 (the first modern constitution in Europe) is proclaimed by the Sejm of Polish–Lithuanian Commonwealth.