#include <bits/stdc++.h>
#include <atcoder/modint>

using namespace std;
using ll = long long;
using namespace atcoder;
using mint = modint998244353;

int main(){
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);

    ll N;
    mint S=0, q, r;
    cin >> N;
    for (int j=1; j<=N; j++){
        //i=kj, kj+1, ... (k+1)j-1はi/j=kでj個
        //N=qj+rと表されるなら0,~,(q-1)がj個
        //qがr+1個ある
        q = N/j;
        r = N%j;
        S += q*(q-1)/2*j;
        S += q*(r+1);
    }
    cout << S.val() << endl;

    return 0;
}