a postal code, a zip code

number (on an athlete's uniform's back); jersey number, uniform number, player number, shirt number

PIN number, PIN

(computing) line number

electromagnetic radiation

individual number, personal identification number, social security number

(Internet slang) person who inflames public anxiety and/or fear with groundless information about radioactivity.

Alternative spelling of 携帯番号 (keitai bangō)

mobile phone number

(physics) radiative cooling