include

using namespace std;

int main() {

int n, k = 1;
cin >>  n;
for (int i = 2; i < n; i++)
{
	if (n % i == 0)
	{
		k = 0;
		cout << -1;
		break;
	}
}
if (k)
{
	cout << 1;
}
return 0;

}