include <bits/stdc++.h>

using namespace std; bool pss(unsigned int n); int main() {

unsigned int n;
cin >> n;
for(int i = 2;i <= sqrt(n);i++)
{
	if(n % i == 0 && pss(i) && pss(n / i))
	{
		cout << n / i << endl;
		return 0;
	}
}
return 0;

} bool pss(unsigned int n) {

if(n == 1) return false;
int t = sqrt(n);
for(int i = 2;i <= t;i++) {
	if(n % i == 0) {
		return false;
	}
}
return true;

}