#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ int n; cin>>n; int i=2; while(i<=n/i){ if(n%i==0){ cout<<"No"<<endl; return 0; } i++; } cout<<"Yes"<<endl; return 0; }