Divisor Sum of 81,081

Example of Sigma Function of Integer

 * $\sigma \left({81 \, 081}\right) = 162 \, 624$

where $\sigma$ denotes the $\sigma$ function.

Proof
We have that:
 * $81 \, 081 = 3^4 \times 7 \times 11 \times 13$

Hence: