Whoever it is, they're spoofing their telephone number because it's not a working number if you call it back. It's most helpful to try to obtain the name, address and a website for the company so they can be identified. Then file a complaint.
This number called today at 8:58 AM, I answered and could hear a lot of background chatter which usually indicated a telemarketer. I am on the donotcall.gov list but it doesn't matter to these people.