import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		long X = scan.nextLong();
		scan.close();
		long x = (long)Math.sqrt(X);
		if(x * x == X) {
			System.out.println(1);
		}else {
			long y = 4;
			long k = 2;
			while(y < X) {
				if(X % y == 0) {
					X = X / y;
				}
				k++;
				y = k * k;
			}
			System.out.println(X);
		}
	}
}