The apartment's ID number tells you which apartment to GO to.
The Bizarro Dentist put a number of pirate hooks in your mouth during the Bizarro Checkup.
|( xxx ) ごう||
a SUFFIX which you put after a numbered item （apartment number, account number, etc.) Like, if you live in room 204, you'd say に ゼロ よん 号。
signal, i.e. traffic signal
your secret PIN number you use when you go to the ATM. This is different from a password you use on the internet - that's パスワード。