Hecho general: 20973 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Hecho matemático: 20973 is a boring number.
Trivia: 20973 is an uninteresting number.
Fecha histórica: June 2nd is the day in 1990 that the Lower Ohio Valley tornado outbreak spawns 66 confirmed tornadoes in Illinois, Indiana, Kentucky, and Ohio, killing 12.