Bill collection agency. They will pretend to be other companies or people as they attempt to "secretly" collect information about a bill dodger. I called them back after a week of random calls and set them straight. Don't give them any of YOUR personal information, just tell them the person does not live/work there and you wish not to be bothered further.
Yes I just received a call from this number and they advised me that they were from the Special Olympics and they wanted a donation and they would take a credit card over the phone! Now that is low! I called back the number and then I was told they made a mistake!! What??? Mistake???They would tell me who they were and hung up on me.