Fatto generale: 1789 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 1789 is the smallest number with the property that its first 4 multiples contain the digit 7.
Trivia: 1789 is a boring number.
Data storica: November 23rd is the day in 1976 that Apneist Jacques Mayol is the first man to reach a depth of 100 m undersea without breathing equipment.