telephone number; phone number
student number (for seating, etc. in class)
personal identification number; PIN; password number
mobile phone number; cell phone number
numbered tag; numbered ticket
number on the back of a player's uniform; uniform number; shirt number; squad number
serial number; consecutive number
(manufacturer's) serial number
account number (bank, etc.)
winning number (e.g. in lottery); lucky number
reference number; serial number
model number; model designation
confirmation number; reservation number; reference number
item number; product ID number; reference number
identification number; confirmation number; authentication number
identity number; national identification number; national identity number; personal identity number
order number; ticket number; tracking number
social security number (USA); SSN
Köchel number (catalogue of Mozart's music)
national identification number system; My number system
directory or book of numbers (e.g. telephone nos)
tracking number (e.g. for orders)
International Standard Book Number; ISBN
reference number; order number; tracking number
number sign; hash sign; pound sign
tax identification number; TIN
(mobile phone) number portability (introduced to Japan in October 2005)
external character number
International Standard Serial Number; ISSN
Post Office box address; P.O.box address
relative generation number
station-to-station (comms)
physical delivery office number
universal pension number; common number shared between different pension schemes; basic pension number
license plate for small vehicles (e.g. subcompact car, motorcycle)
reference number; order number; tracking number
corporate number; 13-digit identification number for corporations
act number (within a year); law number
taxpayer identification number (in the US, Germany, etc.)
region code (e.g. for DVDs); area code (telephone network)