#include <stdio.h>
#include<math.h>
int getNum(long num)
{
    int count = 0;
    while(num)
    {
        num/=10;
        count++;
    }
      return count;
}
int mypow(int n)
{
    int p=1;
    int i;
    for(i= 0;i< n;i++)
    {
        p *=10;
    }
    return p;
}


int main(void)
{
    long  num =0;
    scanf("%d",&num);
    long squre = num*num;

    int n = getNum(num);
    int weishu = squre-num;
    if(weishu%mypow(n)==0)
    {
        printf("yes !\n");
    }
    else
    {
        printf("no !\n");
    }
    return 0;
}