import java.util.Scanner;

public class Yukicoder300 {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long x = sc.nextLong(), y = 1;
        double z;

        for (y = 1; y < x; y++) {
            z = Math.sqrt(x * y);
            if ((int) z == z) break;
        }

        System.out.println(y);
    }
}