180302_2501_약수 구하기

	//https://www.acmicpc.net/problem/2501 #include <iostream>
	using namespace std;
	int main(){
	int N, K;
	cin >> N >> K;
	int cnt=0;
	for(int i=1; i<=N; i++){
	if(N%i==0) cnt++;
	if(cnt==K) {
	cout << i ;
	return 0;
	}
	}
	cout << "0";
	return 0;
	}