Divisor Sum of 14,175

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Example of Divisor Sum of Integer

$\map {\sigma_1} {14 \, 175} = 30 \, 008$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$14 \, 175 = 3^4 \times 5^2 \times 7$


Hence:

\(\ds \map {\sigma_1} {14 \, 175}\) \(=\) \(\ds \dfrac {3^5 - 1} {3 - 1} \times \dfrac {5^3 - 1} {5 - 1} \times \paren {7 + 1}\) Divisor Sum of Integer
\(\ds \) \(=\) \(\ds \dfrac {242} 2 \times \dfrac {124} 4 \times 8\)
\(\ds \) \(=\) \(\ds 121 \times 31 \times 8\)
\(\ds \) \(=\) \(\ds 11^2 \times 31 \times 2^3\)
\(\ds \) \(=\) \(\ds 30 \, 008\)

$\blacksquare$