#include <iostream>
#include <cstring>

using namespace std;

typedef long long LL;

int main(int argc, char *argv[])
{
	LL n;
	cin >> n;
	LL a = n / 1000;
	LL u = 3 * a * a;
	LL l = 3 * 2 * n * (n % 1000);
	u += l / 1000000;
	l %= 1000000;
	if (u > 0) {
		printf("%lld%06lld\n", u, l);
	} else {
		printf("%lld\n", l);
	}
	return 0;
}