#include <stdio.h>
#include <math.h>

int main(void)
{
    long n,t;
    scanf("%ld",&n);
    t=(long)sqrt(2*n);
    if(n==(t*(t+1))/2){
        puts("YES");
        printf("%ld",t);
    }
    else puts("NO");
    return 0;
}