Fatto matematico: 20918 is an unremarkable number.
Trivia: 20918 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: April 8th is the day in 1954 that South African Airways Flight 201 A de Havilland DH.106 Comet 1 crashes into the sea during night killing 21 people.