Who called from 4123520092

I've received 5 calls from this number within the past 2 days.  No one ever answers. Who are these people?? Can they be stopped? These calls are annoying.

Keep getting calls, but no one answers.

I constantly get calls from this number. Sometimes 3 times a day and like everyone says, no one speaks. It's super annoying!

today I received 3 calls from the above number and no one responds. I call back and number out of service so what is going on

Three times on 7/5/12  I have received calls.  No one responds.  When I call back, the number is out of service.  How can that be?  To what purpose are these calls made?  Caller 412352-0092.