Divisor Sum of 6232

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Example of Divisor Sum of Integer

$\map {\sigma_1} {6232} = 12 \, 600$

where $\sigma_1$ denotes the divisor sum function.


Proof

From Divisor Sum of Integer

$\ds \map {\sigma_1} n = \prod_{1 \mathop \le i \mathop \le r} \frac {p_i^{k_i + 1} - 1} {p_i - 1}$

where $n = \ds \prod_{1 \mathop \le i \mathop \le r} p_i^{k_i}$ denotes the prime decomposition of $n$.


We have that:

$6232 = 2^3 \times 19 \times 41$


Hence:

\(\ds \map {\sigma_1} {6232}\) \(=\) \(\ds \frac {2^4 - 1} {2 - 1} \times \paren {19 + 1} \times \paren {41 + 1}\)
\(\ds \) \(=\) \(\ds \frac {15} 1 \times 20 \times 42\)
\(\ds \) \(=\) \(\ds \paren {3 \times 5} \times \paren {2^2 \times 5} \times \paren {2 \times 3 \times 7}\)
\(\ds \) \(=\) \(\ds 2^3 \times 3^2 \times 5^2 \times 7\)
\(\ds \) \(=\) \(\ds 12 \, 600\)

$\blacksquare$