its a prank line. you put someone number in an online database and it calls it with a message. one a got one that yelled into my ear "YOU HAVE THREE DAYS TO LIVE. good bye~~!" and then hung up. it fun and untracable.
Earlier i got the same call from the same exact number..i missed the call so i called back and when i did it was a busy signal so i tried again and it said it wasn't a working number...weird. I don't know where u live but i live in Philly, Pa...I don't get it.