I'm sure that most longer term readers on this list know that the use of the number in the Revelation was a 'code' using the Jewish concept that assigned number values to the letters of the Hebrew alphabet.
A promoter of modern Judaism ( Dr. Eliyahu Lizorkin-Eyzeneberg) explains:
Today gematria is well-known as a Jewish interpretive method that assigns numerical values of Hebrew letters to words, phrases and/or sentences. Then, by adding them together, seeks to determine their deeper meaning. Sometimes that connection is farfetched, but sometimes it is quite clear. But was Gematria also present the New Testament? The answer is a clear yes.
Here are two obvious examples among many.
"In Matthew’s genealogy, which shows that Jesus/Yeshua was a descendent of King David, we read “Thus there were fourteen generations in all from Abraham to David, fourteen from David to the exile to Babylon, and fourteen from the exile to the Messiah.” (Mathew 1:17). The numerical value of the Hebrew characters forming the name of the great King of Israel - David (דוד) is 14."
ד (4) + ו (6) + ד (4).
So what about these numbers in Revelation, which have led to so much ignorant speculation?
Lizorkin-Eyzeneberg comments that:
In the Book of Revelation, we read, “Here is wisdom. Let him who has understanding calculate the number of the beast, for the number is that of a man; and his number is six hundred and sixty-six.” (Rev. 13:18)
Although the beast of the book of Revelation is almost certainly not limited to the first-century, near the time of writing of the Book of Revelation, there was a blood-thirsty persecutor of the early Christ-followers - Nero Caesar, whose name,if counted from Hebrew, had a numeric value of 666. Interestingly, according to tradition, both Peter and Paul were martyred during his reign. It is likely that Nero Caesar was a symbolic figure of all future government-sponsored persecutions.
So that could account for the 666 option, but what about 616?
Here's his answer, in translation, if you apply gematria to Latin,... he argues::
If the original identification of the beast as Emperor Nero is correct, this explains why some early manuscripts of the Book of Revelation have 616 instead of 666 as the number of the beast. This is the numeric value of Emperor Nero's name calculated from Latin.
That explanation came from an email circular that Dr. Eliyahu Lizorkin-Eyzeneberg sends out to promote his version of contemporary Judaism.