import java.util.Scanner;
public class PrimeNumberOrNot {
public static void main(String[] args) {
int c =0;
Scanner in = new Scanner(System.in); //scanner for input
System.out.print("Enter number : ");
int n = in.nextInt();
for(int i=2; i <= (n/2); i++) {
if((n % i) == 0){
c++;
break;
}
}
if((c==0) && (n!= 1)){
System.out.println( n + " prime number.");
}
else {
System.out.println( n+ " not a prime number.");
}
}
}