#include<bits/stdc++.h>
using namespace std;
#define fo(i,a,b) for(int i=a;i<=b;++i)
#define fod(i,a,b) for(int i=a;i>=b;--i)
#define ull __int128
#define ll long long
int z[8]={2,3,5,7,11,13,17,19};
ll ksm(ll x,ll y,ll p){
	if(!x)return 1;
	ull u=ksm(x/2,y,p);
	u=u*u%p;
	if(x&1)u=u*y%p;
	return u;
}
bool Prime(ll x){
	if(x==1)return 0;
	ll t=x-1,k=0;
	while(t%2==0)t/=2,++k;
	fo(i,0,7){
		if(x==z[i])return 1;
		ull a=ksm(t,z[i],x),b=0;
		fo(j,1,k){
			b=a*a%x;
			if(b==1&&a!=1&&a!=x-1)return 0;
			a=b;
		}
		if(b!=1)return 0;
	}
	return 1;
}
int main(){
	ll n;
	while(scanf("%lld",&n)!='EOF'){
		if(Prime(n)){
			puts("Y");
		}
		else puts("N");
	}
	return 0;
}