#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using namespace atcoder;
using mint=modint998244353;

signed main(){
	long long N;
	cin >> N;
	long long M=sqrtl(N);
	mint ans1=0;
	for(int i=1;i<=M;i++){
		ans1+=mint(N/i)*mint(2)-mint(M);
	}
	ans1*=N+1;
	mint ans2=0;
	for(int i=1;i<=M;i++){
		mint k=N/i;
		k*=(k+1);
		k/=2;
		ans2+=mint(i)*k*mint(2)-mint(M)*mint(M+1)/mint(2)*mint(i);
	}
	cout << (ans1-ans2).val() << endl;
}