Fait général: 1724 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 1724 is the number of matroids on 8 points.
Culture générale: 1724 is an unremarkable number.
Date historique: September 19th is the day in 1971 that Montagnard troops of South Vietnam revolt against the rule of Nguyen Khanh, killing 70 ethnic Vietnamese soldiers.