#include<stdio.h>
#include <math.h>

int prime(int n)

{

int i,m;

m=sqrt(n);
for(i=2;i<=m;i++)
if(n%i==0)

return(0);

return(1);

}
int main()
{
int n;
scanf("%d",&n);
if(prime(n))
printf("%d is prime.\n",n);
else
printf("%d is not prime.\n",n);
return 0;
}