Sum of Divisors

By Kay Akashi

Problem Statement

Given an integer $n$, output the sum of divisors of $n$.

In the first example, divisors of $20$ are $(1, 2, 4, 5, 10, 20)$ hence the answer is $1 + 2 + 4 + 5 + 10 + 20 = 42$.

In the second example, divisors of $2022$ are $(1, 2, 3, 6, 337, 674, 1011, 2022)$ hence the answer is $1 + 2 + 3 + 6 + 337 + 674 + 1011 + 2022 = 4056$.

Constraints

$0 \lt n \leq 10^{10}$.

Subtask 1 (30%)

$0 \lt n \lt 100$.

Subtask 2 (30%)

$100 \leq n \lt 10^{5}$.

Subtask 3 (40%)

$10^{5} \leq n \leq 10^{10}$.

Input

Input consists of a single integer, $n$.

Output

Output the answer.

Examples

20

42

2022

4056