import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws Exception {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		sc.close();

		if (n == 1) {
			System.out.println(1);
		} else {
			int cnt = 1;
			for (int i = 100001; ; i++) {
				if (isSosuu(i)) {
					cnt++;
					if (cnt == n) {
						System.out.println((long) i * i);
						return;
					}
				}
			}
		}
	}

	static boolean isSosuu(long n) {
		if (n < 2) return false;
		if (n == 2) return true;
		long end = (int) Math.sqrt(n) + 1;
		for (int i = 2; i <= end; i++) {
			if (n % i == 0) {
				return false;
			}
		}
		return true;
	}
}