#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using ll = long long;
int main () {
	ll N;
	cin >> N;
	ll h = sqrt(N);
	h = max(0ll, h - 10);
	while (h * h <= N) h ++;
	h --;
	mint ans = 0;
	for (ll i = 1; i <= h; i ++) {
		mint q = N / i, r = N % i;
		ans += q * (r + 1);
		ans += (q * (q - 1) * i) / 2;
	}
	ll fl = h + 1;
	while (N / fl >= h) {
		mint q = N / fl, r = N % fl;
		ans += q * (r + 1);
		ans += (q * (q - 1) * fl) / 2;
		fl ++;
	}
	for (ll q = h - 1; q; q --) {
		mint al = (N) / (q + 1) + 1, bt  = N / q;
		mint s = al + bt, d = bt - al + 1;
		ans += d * (N + 1) * q;
		ans -= s * d * q * (q + 1) / 4;
	}
	cout << ans.val() << endl;
}