Fatto generale: 20807 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 20807 is an unremarkable number.
Trivia: 20807 is a boring number.
Data storica: December 18th is the day in 1888 that Richard Wetherill and his brother in-law discover the ancient Indian ruins of Cliff Palace in Mesa Verde.