Math Wiki
Number with color block Red 9


9 (nine) is the integer the proceeds 8 and precedes 10 . The prime factorisation is 3^2. A number is divisible by 9 if the sum of the digits is divisible by 9. 9 is a Square number (i.e. ). 9 ones (1+1+1+1+1+1+1) 9+0 (The identity propety of addition),3*3, (9*1 and 1*9 with the Commutative Propety and the Identity Propety) and 3^2.but if including Decimals/Fraction/Mixed number/Percent,4.5*2/4½*2.

Properties[]

9 = 32.

The sum of the digits of any multiple of 9 is also a multiple of 9. For example: 126 -> 1+2+6 = 9; 136 -> 1+3+6 = 10. 126 is a multiple of 9, and 136 is not.