Fatto matematico: 9403 is 65821 / 7, and each digit is contained in the equation exactly once.
Trivia: 9403 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: September 28th is the day in 1973 that the ITT Building in New York City is bombed in protest at ITT's alleged involvement in the September 11, 1973 coup d'état in Chile.