Just a few notes:
The word antichrist is not a translated word. "antichristos" is a combined form of "christos" - Christ - and the prefix anti. Anti means against, christos is plural not singular so translated it would mean Against Anointed Ones, against the Elect.
The oldest manuscripts have 616 not 666, check the footnotes of your Bible, most usually note the oldest manuscripts. Also recently, a discovered manuscript that turns out to be one of the oldest and was a piece of Revelations and it had the number 616.
Just a couple of notes before everyone goes off the deep end about 666 and antichrist. It's best to do your own research before you start listening to a gazillion opinions.