Translate and number

Well, that's a name of Italian extraction. It might be best to translate it and then go from there (I take it that it's John German or something like that). Or would you prefer a transliteration, e. g. the Gianni name sounded out in Hebrew?

Hebrew letters have numerical significance. E. g. Alef (the first letter is 1), Beth (the second letter) is 2, Gimel (third letter) is 3, etc. But there is not "J" or soft "G" sound so we'd have to improvise.

As you can see, this is far from being an exact science.