That number was spoofed.  See http://en.wikipedia.org/wiki/Caller_ID_spoofing

Just got a call from this number.  We have some Texas interest, so I called it back.  "No longer in service."  So how is it I get a call from a disconnected number?  Spam direct!

A rather rude woman continually calls from this number .
She states she is a Texas a&m student needing to do a survey for a project
but refuses to leave a number or info for a call back.
The people she keeps asking for are in fact so busy they are rarely at their desk physically
and VM is the best way to get a call back (unless it's an emergency).
The number when researched brings up

The Sanchez Oil & Gas Corporation maintains two offices:

Headquarters - Exploration & Production Office
1111 Bagby, Suite 1600
Houston, Texas 77002
( 713 ) - 783 - 8000


Engineering and Administration Office
1920 Sandman
P. O. Box 2986
Laredo, Texas 78044
1 - ( 800 ) - 292 - 7699