#include <bits/stdc++.h>
using namespace std;
using ll=long long;
const ll ILL=2167167167167167167;
const int INF=2100000000;
#define rep(i,a,b) for (int i=(int)(a);i<(int)(b);i++)
#define all(p) p.begin(),p.end()
template<class T> using _pq = priority_queue<T, vector<T>, greater<T>>;
template<class T> int LB(vector<T> &v,T a){return lower_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> int UB(vector<T> &v,T a){return upper_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> bool chmin(T &a,T b){if(b<a){a=b;return 1;}else return 0;}
template<class T> bool chmax(T &a,T b){if(a<b){a=b;return 1;}else return 0;}
template<class T> void So(vector<T> &v) {sort(v.begin(),v.end());}
template<class T> void Sore(vector<T> &v) {sort(v.begin(),v.end(),[](T x,T y){return x>y;});}
bool yneos(bool a,bool upp=false){if(a){cout<<(upp?"YES\n":"Yes\n");}else{cout<<(upp?"NO\n":"No\n");}return a;}
template<class T> void vec_out(vector<T> &p,int ty=0){
    if(ty==2){cout<<'{';for(int i=0;i<(int)p.size();i++){if(i){cout<<",";}cout<<'"'<<p[i]<<'"';}cout<<"}\n";}
    else{if(ty==1){cout<<p.size()<<"\n";}for(int i=0;i<(int)(p.size());i++){if(i) cout<<" ";cout<<p[i];}cout<<"\n";}}
template<class T> T vec_min(vector<T> &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmin(ans,x);return ans;}
template<class T> T vec_max(vector<T> &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmax(ans,x);return ans;}
template<class T> T vec_sum(vector<T> &a){T ans=T(0);for(auto &x:a) ans+=x;return ans;}
int pop_count(long long a){int res=0;while(a){res+=(a&1),a>>=1;}return res;}
template<class T> T square(T a){return a * a;}

#include <atcoder/modint>
using mint = atcoder::modint998244353;

void solve();
// CITRUS CURIO CITY / FREDERIC
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t = 1;
    // cin >> t;
    rep(i, 0, t) solve();
}

void solve(){
    ll N;
    cin >> N;
    mint ans = 0;
    /*rep(s, 1, N + 1) rep(t, s, N + 1){
        ll tmp = (N - s) / t - s;
        ans += max(0ll, tmp) * s;
    }*/
    vector<ll> L(1), R(1);
    for (ll s = 1; s * s <= N; s++){
        ll l = s;
        // (N - s) / t - s >= 0
        // N - s >= s * t
        // (N - s) / s >= t
        ll r = (N - s) / s + 1;

        /*
        mint tmp = 0;
        for (ll k = l; k < r; k++){
            tmp += (N - s) / k;
        }
        ans -= s * s * (r - l);
        ans += tmp * s;
         */

        if (l >= r) break;
        L.push_back(l);
        R.push_back(r);
        ans -= s * s * (r - l);
    }
    if ((int)L.size() == 1){
        cout << "0\n";
        return;
    }
    mint inv2 = 2;
    inv2 = inv2.inv();
    ll lim = L.back();
    // 1 ~ lim
    for (ll t = 1; t <= lim; t++){
        // rep(s, 1, t + 1) ans += ((N - s) / t) * s;
        ll tmpl = 1;
        while (tmpl != t + 1){
            ll v = (N - tmpl) / t;
            ll tmpr = N - v * t;
            chmin(tmpr, t);
            ans += (mint)((N - tmpl) / t) * (mint)(tmpl + tmpr) * (mint)(tmpr - tmpl + 1) * inv2;
            tmpl = tmpr + 1;
        }
    }
    // cout << ans.val() << "\n";
    // (lim + 1) ~ (N - 2)
    /*
    mint v1 = ans;
    for (ll s = 2; s <= lim; s++){
        for (ll t = lim + 1; t < R[s]; t++){
            ans += (N - s) / t * s;
            cout << t << " " << (N - s) / t * s << "\n";
        }
    }
    cout << (ans - v1).val() << "\n";
    v1 = ans;*/
    ll v_max = (N - 1) / (lim + 1);
    for (ll v = 1; v <= v_max; v++){
        // ans -= (mint)(v) * (mint)(1 + v) * (mint)(lim) * inv2;
        ll l = 1;
        while (l <= v){
            ll t = (N - l) / v;
            if (t <= lim) break;
            // t * v = N - l
            ll r = N - t * v;
            chmin(r, v);
            // cout << v << " " << t << " ";
            // cout << ans.val() << endl;
            ans += (mint)(r - l + 1) * (r + l) * inv2 * (t - lim);
            l = r + 1;
        }
    }
    rep(s, 1, lim + 1){
        ans += (mint)(s - 1) * (mint)(s) * (R[s] - 1 - lim);
    }
    cout << ans.val() << "\n";
}