text: /**
  *
  * Author: Gabriel Clavero
  * Homepage: https://github.com/gabrielclavero/gc-acm-solutions
  *
  */
  
  #include <iostream>
  #include <cmath>
  
  using namespace std;
  
  int main(void)
  {
  	unsigned long n, divisores;
  	
  	cin >> n;
  	while(n !=0) {
  		double tmp = sqrt((double) n);
  		if(fabs(floor(tmp) - tmp) <= 0.0001 && (n % (int) tmp == 0))
  		    cout << "yes" << endl;
  		else
  		    cout << "no" << endl;
  
  		cin >> n;
  	}
  
  	return 0;
  }
  