Divisor Sum of 81,081

Example of Divsor Sum of Integer

 * $\map {\sigma_1} {81 \, 081} = 162 \, 624$

where $\sigma_1$ denotes the divsor sum function.

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

Hence: