Isopsephy

Definition: the Greek analogue of gematria — summing the numerical values of letters of the Greek alphabet; considered the predecessor of gematria. According to Aristotle, the Pythagorean tradition (founded in the 6th century BC) practiced isopsephy; the Milesian system of letter-numbers was in common use by the time of Alexander the Great. Example: the name Nero (Νερων) = 1005, which equals "killed his mother"; inscriptions found in Pompeii read "I love her whose number is 545."

[source: Isopsephy — Wikipedia (en); Numerology — Wikipedia (en)] Related: gematriya, Pythagorean numerology, arifmantika.