#include<bits/stdc++.h>
#define shahin std::ios_base::sync_with_stdio(false); std::cin.tie(NULL);
#define ll long long
#define pb push_back
const int nax=1000*1007;
const int mod = 1e9 + 7;
#define F first
#define S second
const int mx = 1e6 +10;
bool prime[mx];
using namespace std;
void fun1()
{
prime[1]=1;
for(ll i=4;i<=mx;i+=2){
prime[i]=1;
}
for(ll i=3;i<=sqrt(mx);i+=2){
if(prime[i]==0){
for(ll j=i*i;j<mx;j+= i*2){
prime[j]=1;
}
}
//prime[i]=1;
}
}
void fun()
{
fun1();
ll n;
while(cin >>n && n!=0){
string s = to_string(n);
reverse(s.begin(),s.end());
ll a = stoll(s);
if(prime[n]==0){
if(prime[a]==0 && n!=a)cout <<n<<" is emirp.\n";
else cout <<n << " is prime.\n";
}
else cout << n <<" is not prime.\n";
}
}
int main()
{
shahin
/*int tc,i=1;
cin >> tc;
while(tc--)
{
//cout << "Case #" << i << ": ";
fun();
//i++;
} */
fun();
}
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