General fact: 15219 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Mathematical fact: 15219 is an uninteresting number.
Trivia: 15219 is an unremarkable number.
Historical date: August 31st is the day in 1803 that Lewis and Clark start their expedition to the west by leaving Pittsburgh, Pennsylvania at 11 in the morning.