Number Formed by Any Power

The sum of the digits of a number formed by any power or index of 9 is always 9.

(i) 9² = 9 x 9 = 81 → 8 + 1 = 9

(ii) 9³ = 9 x 9 x 9 = 729 → 7 + 2 + 9 = 18 → 1 + 8 = 9

(iii) 9⁴ = 9 x 9 x 9 x 9 = 6561 → 6 + 5 + 6 + 1 = 18 → 1 + 8 = 9

(iv) 9⁵ = 9 x 9 x 9 x 9 x 9 = 59049 → 5 + 9 + 0 + 4 + 9 = 27 → 2 + 7 = 9

(v) 9 x 7 = 63 → 6 + 3 = 9

(vi) 9 x 15 = 135 → 1 + 3 + 5 = 9

(vii) 9 x 17 = 153 → 1 + 5 + 3 = 9

(viii) 9 x 19 = 171 → 1 + 7 + 1 = 9

Related Concept

● Patterns and Mental Mathematics

● Counting Numbers in Proper Pattern

● Odd Numbers Patterns

● Three Consecutive Numbers

● Number Formed by Any Power

● Product of The Number

● Magic Square