Mathematical fact: 917 is the only positive number known whose 9^{th} power can be written as the sum of ten 9^{th} powers.
Trivia: 917 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Historical date: July 5th is the day in 1999 that U.S. President Bill Clinton imposes trade and economic sanctions against the Taliban regime in Afghanistan.