Fait mathématique: 6419 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Culture générale: 6419 is an uninteresting number.
Date historique: July 28th is the day in 1932 that U.S. President Herbert Hoover orders the United States Army to forcibly evict the "Bonus Army" of World War I veterans gathered in Washington, D.C.