Fatto matematico: 4093 is 28651 / 7, and each digit is contained in the equation exactly once.
Trivia: 4093 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: March 16th is the day in 455 that Emperor Valentinian III is assassinated by two Hunnic retainers while training with the bow on the Campus Martius (Rome).