I think this is an outbound only line that is an extension from a calling card service or major switchboard.  So for example, lets say your from korean guy, and your making a phone call using a phone card; the phone cards outbound number to wherever he dialed will show up as that number. So it can be potentially anyone whos calling you.

mr know it all, nice try!
Bwahahahahahahahaha

mr know it all, nice try!Bwahahahahahahahaha

some russian guy calls

who is this f***?!

who is this???