Fatto matematico: 4003 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 4003 is an unremarkable number.
Data storica: December 16th is the day in 1997 that an episode of Pokémon, "Dennō Senshi Porygon", aired in Japan induces seizures in 685 Japanese children.