Divisor Sum of 64

Example of Divisor Sum of Integer

$\map {\sigma_1} {64} = 127$

where $\sigma_1$ denotes the divisor sum.

Proof

We have that:

$64 = 2^6$

Hence:

\(\ds \map {\sigma_1} {64}\)

\(=\)

\(\ds 2 \times 7 - 1\)

Divisor Sum of Power of 2

\(\ds \)

\(=\)

\(\ds 127\)

$\blacksquare$