I believe this is a Robo call using a block of dead numbers as fast as possible before being caught. The number was disconnected the minute that I called it back.  As of today, it is still listed as disconnected.
Numbers used to date:
210-213-7630
210-224-6452
210-224-2189
210-829-3491
210-226-1140

Same answer here as with the other thread.. A lot of this is not being disconnected as soon as you call it back, it was never live to begin with. Its called call spoofing!
phone spoofing explanation
http://en.wikipedia.org/wiki/Spoofing_attack
http://www.fcc.gov/guides/caller-id-and-spoofing
*****************
http://consumerist.com/2014/03/18/florida-den ... y-telemarketer/
http://800notes.com/forum/ta-9f0ce767d8019be/a-different-spoofing-victim
http://www.foxnews.com/us/2014/07/26/colorado ... er-id-spoofing/

In most cases, you best bet is to block the area code. Newer models of blocking devices allow to block by area codes.

called...no message...blocked!