#include<stdio.h>
#include<math.h>
int main()
{
    int i;
    scanf("%d",&i);

    if(i%2==0)
    {
        printf("No\n");  //2 diye vag gele prime na
        goto A;
    }
    for(int a = 3 ; a<sqrt(i) ; a=a+2) 
        /* prime number square root porzonoto hisab korlei hoy
        r dui diye vag jabe na mne bijor korlei hobe */
    {
        if(i%a==0){
            printf("No\n");
            goto A;
        }
    }
    printf("Yes\n");
    A: return 0;


}