Fatto generale: 20019 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 20019 is an unremarkable number.
Trivia: 20019 is a boring number.
Data storica: October 22nd is the day in 1910 that Dr. Crippen is convicted at the Old Bailey of poisoning his wife and is subsequently hanged at Pentonville Prison in London.