123-456-5443

OK so now ADT security service is calling from this number. I assume it to be a VoIP type of number due to the 123-456-.... beginning of the number. Rather odd. Anyways my roommate answered the phone and said we already have a security service at which point the caller hung up. I told her next time if she remembers to ask this service if they can top "killer dust bunnies" as a security service.... heheh. Beware out there.

ADT only calls from 800 numbers that are listed to them.  These are scammers pretending to be ADT.

Plus, there's no such area code right?

It might exist somewhere in the world, but not in the North American Numbering Plan.

Recently started getting calls from this number . . . Lucky me, eh?  There is no area code 123.