What if there were no such things as Arabic numerals (0123456789)?
What if you only had your alphabet?
You could use letters as numerical values. (A=1 B=2 C=3, etc. etc.) (B+B=D means 2+2=4) Get it? Sure ya do.
In Greek (Alpha=1, Beta=2, Gamma=3, etc.)
This is what HEBREW and GREEK and ROMAN alphabets offered: no (separate symbols) numerals, only letters.
So what?
Well, suddenly things get interesting!! A string of numbers might co-incidentally also be a word....an interesting phenomena to mathematically inclined crackpots! People of a certain frame of mind (obsessive compulsive mathemeticians, idiot-savants, religious nuts, etc.)
Read on........this is called GEMATRIA.
Quite a craze developed among religious savants (i.e. smart fanatics with too much time on their hands) to interpret words in light of their numerical value and interpret numerical value in light of the corresponding words.
The Roman God JOVE was represented by the Roman letters IV. To avoid desecrating JOVE'S name, Grandfather clocks don't abbreviate 4 as IV but as four one's IIII. Ever notice that and wonder why there was no IV?
Silly, but, widely attested to in pseudoepigrapha (Gospels written by someone other than by the Author of attestation).
Ceasar Nero's value was 666. Ring a bell?
Christian scribes often didn't write the word AMEN, but, only the numerical value of 99.
Fun?