Hecho general: 1690 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Hecho matemático: 1690 is the number of ordered sequences of coins totaling 27 cents.
Trivia: 1690 is an uninteresting number.
Fecha histórica: August 16th is the day in 1927 that the Dole Air Race begins from Oakland, California, to Honolulu, Hawaii, during which six out of the eight participating planes crash or disappear.