This is not even a valid number so therefore you can safely assume it is one of those annoying telemarketers who do not respect the Do Not Call list and by not providing a valid callback number you will never be able to report them to the FCC
Asked if an agent could call in a few days about life insurance. When I asked if this call was in accordance to the Federal No Call List, the caller didn't really know what I was talking about (he had what sounded like an Indian accent and it was obvious it was a call center ... though the caller ID was California, the call-back had the number as not in service.) I asked the same question several ways, and he went on with the question if it was okay to have someone call. I finally said this call is "illegal" and he hung up.