Divisor Sum of 19,116

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Example of Divisor Sum of Integer

$\map {\sigma_1} {19 \, 116} = 50 \, 820$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$19 \, 116 = 2^2 \times 3^4 \times 59$

Hence:

\(\ds \map {\sigma_1} {19 \, 116}\) \(=\) \(\ds \frac {2^3 - 1} {2 - 1} \times \frac {3^5 - 1} {3 - 1} \times \paren {59 + 1}\) Divisor Sum of Integer
\(\ds \) \(=\) \(\ds 7 \times 121 \times 60\)
\(\ds \) \(=\) \(\ds 7 \times 11^2 \times \paren {2^2 \times 3 \times 5}\)
\(\ds \) \(=\) \(\ds 50 \, 820\)

$\blacksquare$