Fatto generale: 20398 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 20398 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 20398 is an uninteresting number.
Data storica: November 5th is the day in 1743 that Coordinated scientific observations of the transit of Mercury are organized by Joseph-Nicolas Delisle.