Fatto generale: 99109 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 99109 is an unremarkable number.
Trivia: 99109 is a boring number.
Data storica: May 8th is the day in 1976 that the rollercoaster Revolution, the first steel coaster with a vertical loop, opens at Six Flags Magic Mountain.