General fact: 387 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Mathematical fact: 387 is the smallest number with sort-then-add persistence of 10.
Trivia: 387 is an uninteresting number.
Historical date: January 21st is the day in 1908 that New York City passes the Sullivan Ordinance, making it illegal for women to smoke in public, only to have the measure vetoed by the mayor.