Fatto generale: 20123 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 20123 is an uninteresting number.
Trivia: 20123 is a boring number.
Data storica: February 3rd is the day in 1900 that Governor of Kentucky William Goebel dies of wound sustained in an assassination attempt three days earlier in Frankfort, Kentucky.