Someone mentioned 616 as an alternative reading to 666.  In case anyone is wondering about that, here's some thoughts on why I doubt 616:
 
616 vs. 666: Which Is the Real Number of the Beast?
http://www.escapeallthesethings.com/666-616-number-mark-of-the-beast.htm
 
Hope this helps,
 
Tim McHyde
http://www.EscapeAllTheseThings.com
Sharing the Plainterpretation of Bible Prophecy since 2000