math_fact: 8657 is the number of ways to tile a 4×30 rectangle with 4×1 rectangles.
trivia: 8657 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
historical_date: September 13th is the day in 533 that General Belisarius of the Byzantine Empire defeats Gelimer and the Vandals at the Battle of Ad Decimium, near Carthage, North Africa.