666: This is derived from the Greek spelling of Nero's name, "Neron Kaisar" (Νέρων Καῖσαρ), which when transliterated into Hebrew letters (n-r-w-n q-s-r) equals 666.
616: This is derived from the Latin spelling of the name, "Nero Caesar," which when transliterated into Hebrew letters (n-r-w-q-s-r) equals 616.
