#include<stdio.h>
void main()
{
	int x; 
 	scanf("%d",&x); 
	if(x != 1){ 
 	int i; 
 	int c = 0; //除了1很本身外的约数 
	for(i = 2;i <= x/2 ;i++){ 
		if(x % i == 0){ 
 			c++; 
 			printf("%d",i);
 			break; 
 		} 
	} 
 
 	if(c == 0){ 
 		printf("Yes");
 	}
	}
}
/**************************************************************
	Problem: 1061
	User: admin
	Language: C
	Result: Accepted
	Time:9 ms
	Memory:1144 kb
****************************************************************/