#include <cstdio>
#include <iostream>

#define rep( i, n, m ) for (int i = ( n ); i < ( m ); i++)
#define rep_d( i, n, m ) for (int i = ( n ); i < ( m ); i--)

int main( void ){
	unsigned long long n;
	// if(!scanf( "%ld", &n ))
	//  return -1;
	std::cin >> n;
	if (n == 1){
		printf( "1\n" );
		return 0;
	}
	unsigned long long sum = 1 + n;
	unsigned long long max = n;
	unsigned long long a;
	// if (n % 2 == 0){
	//  sum += ( int )( n / 2 ) + 2;
	//  if (n == 4){
	//      sum-=2;
	//  }
	// }
	for(unsigned long long i = 2; i < max; i++){
		a = ( unsigned long long )( n / i );
		if (n - i * a == 0){
			sum += i + a;
			max = a;
			if (a == i)
				sum -= i;
		}
	}
	std::cout << sum << std::endl;
	return 0;
}