#include<iostream>
#include<cmath>
using namespace std;
long long a,gs=0;
int main()
{
	cin>>a;
	for(int i=1; i<a; i++)
	{
		if(a%i==0) gs+=i;
	}
	if(gs==a) cout<<"yes";
	else cout<<"no";
    return 0;
}
/**************************************************************
	Problem: 1859
	User: admin
	Language: C++
	Result: Accepted
	Time:366 ms
	Memory:2072 kb
****************************************************************/