Fatto generale: 1939 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 1939 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 1939 is an uninteresting number.
Data storica: April 22nd is the day in 1529 that Treaty of Saragossa divides the eastern hemisphere between Spain and Portugal along a line 297.5 leagues or 17° east of the Moluccas.