General fact: 4486 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Mathematical fact: 4486 is an uninteresting number.
Trivia: 4486 is an unremarkable number.
Historical date: April 12th is the day in 1937 that Sir Frank Whittle ground-tests the first jet engine designed to power an aircraft, at Rugby, England.