Board Thread:General Discussion/@comment-28125426-20170119074645/@comment-1257201-20170120072632

If you're referring to the Biblical use of the number, the issue is not translation. Most ancient Greek manuscripts of the Book of Revelation give the number as six-hundred sixty six, but a few ancient manuscripts give it as six-hundred sixteen. The theory that this represents Nero[n] has been suggested by some scholars, but "most commonly believed" is too strong: there are plenty of scholars who disagree, both secular and Christian.

As far as DC is concerned, this is a bit silly, because the Gematria for Nero[n] Caesar (transliterated from Latin to Aramaic) gives 616, and the Gematria for the same name transliterated from Latin to Greek to Aramaic gives 666. But the demon Neron in DC Comics is simply "Neron", not "Neron Caesar", so none of this applies to him.