Fait général: 2811 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 2811 is the number of inequivalent Ferrers graphs with 30 points.
Culture générale: 2811 is an uninteresting number.
Date historique: September 11th is the day in 1973 that a coup in Chile headed by General Augusto Pinochet topples the democratically elected president Salvador Allende.