After the fall of the Roman empire in the middle ages, the letter "S" was attributed to 7 and 70.

Using roman numerals not gematria
with 7
six six six = ( 7+ 1 + 10 ) + ( 7+ 1 + 10 ) + ( 7+ 1 + 10 ) = 54 (9 digits to 54) divide 54 by 9 you get = 6


with 70
(70+1+10) +(70+1+10) +(70+1+10)= 81+81+81 = 243 81 is the perfect square of 9 - flip it in the mirror now....