I'll catch that fish. It has my number on it.
Shore folk think sailors are heartless, and that when a poor chap is lost overboard, they only say that So-and-so has lost the number of his mess! and, after having an auction over his kit in the fo'c's'le, then dismiss him from their memory! — J.C. Hutcheson, Fritz and Eric, 1880.
Commuting to work is the number one reason to own a car.
... So lame argument number one, for example, ...
... Because number one, they want to see what's going on next. ...