9 times 9 times 9 = 729
7+2+9 = 18
1+8 = 9!
9+9 = 18
1+8 = 9!
9+9+9+9 = 36
3+6 = 9!
You see, no matter how many times you multiply nine, when you take the number to its most basic form, you get nine! What a weird and nifty number. No wonder it's significant in many cultures. For my part, my favorite/lucky number is three, which is a divisor of nine!
But from a Jewish view, the number 9 is the gematria (calculation of numerical value of words according to corresponding letter/number values) of the word emet, or truth. And the word emet -- composed of aleph, mem, tav -- is interesting and beautiful in and of itself, because the first letter (aleph) is the first letter of the Hebrew alphabet, the second letter (mem) is the middle letter of the alphabet, and the last letter (tav) is the last letter of the alphabet.
The point? Just as the word truth encompasses all things, from beginning, middle, to end (as in emet), so too the gematria of the word expresses this, because all multiples and additions of nine to nine always come back to, well, nine. To truth. No matter what road you take, if you start with truth, you end with truth, because it is found in all things.
Beautiful, no? I wrote about this concept of emet in the past, but not this beautiful thing with the number nine.