#include <iostream>

using namespace std;

int input, i = 2;

// This assignment is worth 4 points

int main()
{
	do
	{
		cout << "Enter number: ";
		cin >> input;
		cin.ignore();
		if(input < 2)
			cout << "Error - input must be greater than 1\n";
	} while(input < 2);

	while(input % i != 0)
		i++;

	if(i < input)
		cout << input << " is not a prime number.\n";
	else
		cout << input << " is a prime number.\n";

	return 0;
}