Fait mathématique: 7854 is a number whose sum of divisors is a 4^{th} power.
Culture générale: 7854 is an unremarkable number.
Date historique: July 2nd is the day in 1853 that the Russian Army crossed the Pruth river into the Danubian Principalities, Moldavia and Wallachia—providing the spark that set off the Crimean War.