#include <bits/stdc++.h>
using namespace std;
using ll = long long;
ll C(int a) {
	// a個の中から4つ選ぶ
	ll x = (a*(a-1ll))/2ll;
	ll y = ((a-2ll)*(a-3ll))/2ll;
	if (x%3ll == 0ll) {
	  x /= 3ll;
	}
	else {
	  y /= 3ll;
	}
	if (x%2ll == 0ll) {
	  x /= 2ll;
	}
	else {
	  y /= 2ll;
	}
	return (x%998244353ll)*(y%998244353ll);
}
int main() {
	int a;
	cin >> a;
	ll ans;
	ans = C(a);
	for (int i = 4; i < a; i++) {
	    ans = (ans%998244353ll);
    	ans *= 26ll;
		ans = (ans%998244353ll);
	}
	cout << ans << endl;
	return 0;
}