Fatto generale: 16559 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 16559 is a boring number.
Trivia: 16559 is an uninteresting number.
Data storica: May 2nd is the day in 1964 that First ascent of Shishapangma the fourteenth highest mountain in the world and the lowest of the Eight-thousanders.