I'm also getting constant calls from this number! Don't blame the Do Not Call list! That is set up for legitimate businesses, and it does work with them. There is nothing legitimate about any of these callers!!!
Steve in MA is partially correct. Toll-free calls are in reality collect calls charged to the called party. In the days before most people had unlimited long distance the phone companies had to know how much to charge the receiving party for the "toll free" call. For this reason these numbers were always exempt from call-blocking.