This has a lot of problems, and conflicts with https://en.wikipedia.org/wiki/Telephone_numbering_plan#Area_code by its title (local dialing code) ,and description. (identifier dedicated to subject city by the area communication network). it is so messed up in infoboxes as phone code vs area code.Wikidata:Property_proposal/Archive/6#P473 .
and in the examples (812) and (02) are area codes.it all started as https://www.wikidata.org/w/index.php?title=Property:P473&oldid=32001351 and has evolved in too the wrong thing.,local calling code, telephone prefix, local dialling code, Subscriber trunk dialling (STD).