It's from the Portable North Pole, a program either on your (or a loved ones) computer or phone, set up to call your children, and occasionally adults, to wish you a merry Christmas and various other messages from Santa Clause and his elves. Someone has paid for this service to entertain your children, if not you. If you paid for such a service and thought you'd see "Santa" on the call tag, your not going to get it, only this number. Check your emails, you may have a video mail as well. Not a scam, not a prank call, not a perv, just Santa (who's kind of a perv...he sees you when you're sleeping? )