#include <bits/stdc++.h>
using namespace std;
const long long MOD = 998244353;
int main(){
  int N;
  cin >> N;
  vector<long long> inv(N + 1);
  inv[1] = 1;
  for (int i = 2; i <= N; i++){
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
  }
  vector<long long> fact(N + 1), finv(N + 1);
  fact[0] = 1;
  finv[0] = 1;
  for (int i = 1; i <= N; i++){
    fact[i] = fact[i - 1] * i % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
  vector<long long> pow25(N + 1);
  pow25[0] = 1;
  for (int i = 0; i < N; i++){
    pow25[i + 1] = pow25[i] * 25 % MOD;
  }
  long long ans = 0;
  for (int i = 0; i <= N; i++){
    ans += fact[N] * finv[i] % MOD * finv[N - i] % MOD * pow25[N - i] % MOD * (i / 3) % MOD;
  }
  ans %= MOD;
  cout << ans << endl;
}