Fatto generale: 6688 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 6688 is a boring number.
Trivia: 6688 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: April 23rd is the day in 1955 that the Canadian Labour Congress is formed by the merger of the Trades and Labour Congress of Canada and the Canadian Congress of Labour.