Got a call from this number yesterday (2/17/2017) at around 3 PM.  Caller ID showed up as "AMERICAN AFF 1-720-577-5036".  I let the call roll thru to voice mail.  Whoever it was didn't leave any message. The next morning I tried calling the number back (using *67 to block my own CID).  I got a recorded message that "The number you have dialed is not in service." Added this number to my phone's Call Block List.