#include <iostream>
#include <cassert>

long long s(long long n){
	long long ret = 1;
	for(long long i=2; i*i<=n; i++){
		if(n%i != 0) continue;
		long long tmp = i;
		while(n%i == 0){
			tmp *= i;
			n /= i;
		}
		ret *= (tmp-1)/(i-1);
	}
	if(n!=1){
		ret *= n+1;
	}
	return ret;
}

int main(){
	long long n;
	std::cin >> n;
	assert(1<=n && n<=2000000000000);
	std::cout << (n&1?s(n):s(n/2)) << std::endl;
}