Fatto generale: 21868 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 21868 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 21868 is a boring number.
Data storica: November 14th is the day in 1967 that American physicist Theodore Maiman is given a patent for his ruby laser systems, the world's first laser.