Fait mathématique: 18166 is an uninteresting number.
Culture générale: 18166 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Date historique: September 25th is the day in 1804 that the Teton Sioux (a subdivision of the Lakota) demand one of the boats from the Lewis and Clark Expedition as a toll for moving further upriver.