#include using namespace std; typedef long long ll; #define MAX 1000010 const int MOD = 998244353; bool is_prime[MAX]; ll mu[MAX]; vector prime_table() { is_prime[2] = true; for (int n = 3; n < MAX; n += 2) { is_prime[n] = true; } for (int p = 3; p * p < MAX; p += 2) { if (is_prime[p]) { int q = p * p; for (int i = q; i < MAX; i += p) { is_prime[i] = false; } } } vector primes; for (int p = 0; p < MAX; p++) { if (is_prime[p]) { primes.emplace_back(p); } } return primes; } void mobius_table(vector primes) { for (int n = 1; n < MAX; n++) { mu[n] = 1; } for (int i = 0; i < primes.size(); i++) { ll p = primes[i]; for (int j = p; j < MAX; j += p) { mu[j] *= (-1); } ll q = p * p; if (q >= MAX) continue; for (int j = q; j < MAX; j += q) { mu[j] = 0; } } } ll F(ll N) { ll x_max = sqrt(N); ll S = 0; for (ll x = 1; x <= x_max; x++) { ll y_max = sqrt(N - x * x); S += x * (1 + 2 * y_max); S %= MOD; } return S; } ll f(ll N) { ll ret = 0; for (ll d = 1; d <= N; d++) { ll n = N / (d * d); if(n == 0){ break; } ret += F(n) * mu[d] * d % MOD; } ret %= MOD; ret *= 24; ret -= 16; ret %= MOD; if (ret < 0) ret += MOD; return ret; } int main() { ll N; cin >> N; vector primes = prime_table(); mobius_table(primes); cout << f(N) << endl; return 0; }