Fatto matematico: 6918 is 20754 / 3, and each digit is contained in the equation exactly once.
Trivia: 6918 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: December 9th is the day in 1950 that Harry Gold is sentenced to 30 years in jail for helping Klaus Fuchs pass information about the Manhattan Project to the Soviet Union.