According to the guy in-game who tells you the IV's of a pokémon, my Zygarde has 31 IV in all stats, except attack.
I guess this will make it easy for you to determine the base stats.
No EV's, I put it in PC after capture.
http://i.imgur.com/fJwD2po.jpg
http://i.imgur.com/6epMTvL.jpg