General fact: 1784 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Mathematical fact: 1784 is a number n for which f(n) is a repdigit.
Trivia: 1784 is a boring number.
Historical date: November 18th is the day in 1930 that Soka Kyoiku Gakkai, a Buddhist association later renamed Soka Gakkai, is founded by Japanese educators Tsunesaburo Makiguchi and Josei Toda.