#include<stdio.h>
#include<math.h>
int main()
{
int a, k, i, m;
i =2;
scanf("%d", &a);
k = sqrt(a);
if (a > 2)
{
int z=1;
for (i; i <= k; m = a % i)
{
if (m ==0)
z = 0;
break;
i++;
};
switch (z)
{
case 0:
printf("非素数\n");
break;
case 1:
printf("素数\n");
break;
}
}
else
printf("素数\n");
}