Fait mathématique: 23978 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Culture générale: 23978 is an unremarkable number.
Date historique: August 24th is the day in 1933 that the Crescent Limited train derails in Washington, D.C., after the bridge it is crossing is washed out by the 1933 Chesapeake–Potomac hurricane.