Fatto generale: 21123 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 21123 is a boring number.
Trivia: 21123 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: October 30th is the day in 1960 that Michael Woodruff performs the first successful kidney transplant in the United Kingdom at the Edinburgh Royal Infirmary.