You might have heard about "Hebrew Gemetry" (Gematria), especially when related to Kabalah (קבלה) or other Jewish religious streams.
The concept is very easy to understand, every letter in Hebrew also represents a number.
In Ancient Hebrew, this method was used in order to count,
today Gematria is mainly used for the Hebrew Calendar and Numerology.
1 - א
2 - ב
3 - ג
4 - ד
5 - ה
6 - ו
7 - ז
8 - ח
9 - ט
10 - י
20 - כ
30 - ל
40 - מ
50 - נ
60 - ס
70 - ע
80 - פ
90 - צ
100 - ק
200 - ר
300 - ש
400 - ת
500 - ך
600 - ם
700 - ן
800 - ף
900 - ץ
How to count words
It's easy, sum all the letters in the word to get the number
example:
ישראל = י + ש + ר + א + ל
10 + 300 + 200 + 1 + 30 = 541