#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
    int n;
    ll ans = 0;
    cin >> n;
    for(int i = 1; i <= n; i++){
        int div = n / i, r = n - div * i;
        ans += i * (ll)(div - 1) * div / 2 + (ll)(r + 1) * div;
    }
    cout << ans % 998244353 << '\n';
}