#include <iostream>
#include <string>
#include <algorithm>
#include <numeric>
#include <set>
using namespace std;
int main(){
	string s;
	cin >> s;
	set<long long> st;
	long long mod = 1000000;
	for (long long i = 1; i <= 1000000;i++){
		st.insert((i*i)%mod);
	}
	long long x = stoll(s);
	if (st.count(x)){
		cout << "YES\n";
	}
	else cout << "NO\n";
	
	
	return 0;
}