Divisor Sum of 45,045

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Example of Divisor Sum of Integer

$\map {\sigma_1} {45 \, 045} = 104 \, 832$

where $\sigma_1$ denotes the divisor sum function.


Proof

We have that:

$45 \, 045 = 3^2 \times 5 \times 7 \times 11 \times 13$


Hence:

\(\ds \map {\sigma_1} {45 \, 045}\) \(=\) \(\ds \dfrac {3^3 - 1} {3 - 1} \times \paren {5 + 1} \times \paren {7 + 1} \times \paren {11 + 1} \times \paren {13 + 1}\) Divisor Sum of Integer
\(\ds \) \(=\) \(\ds \dfrac {26} 2 \times 6 \times 8 \times 12 \times 14\)
\(\ds \) \(=\) \(\ds 13 \times 6 \times 8 \times 12 \times 14\)
\(\ds \) \(=\) \(\ds 13 \times \paren {2 \times 3} \times 2^3 \times \paren {2^2 \times 3} \times \paren {2 \times 7}\)
\(\ds \) \(=\) \(\ds 2^7 \times 3^2 \times 7 \times 13\)
\(\ds \) \(=\) \(\ds 104 \, 832\)

$\blacksquare$