import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		int N = scan.nextInt();
		int K = scan.nextInt();
		scan.close();
		if(K == 1) {
			System.exit(0);
		}
		int ans = 1;
		for(int i = N - 1; i >= 2; i--) {
			if(N % i == 0) {
				ans = i;
				break;
			}
		}
		System.out.println(ans);
	}
}