#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
using namespace std;
using std::cout;
using std::cin;
using std::endl;
using ll=long long;
using ld=long double;
ll I=1167167167167167167;
ll Q=998244353;
#define rep(i,a) for (ll i=0;i<a;i++)
template<class T> using _pq = priority_queue<T, vector<T>, greater<T>>;
template<class T> ll LB(vector<T> &v,T a){return lower_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> ll UB(vector<T> &v,T a){return upper_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> bool chmin(T &a,const T &b){if(a>b){a=b;return 1;}else return 0;}
template<class T> bool chmax(T &a,const 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;});}
template<class T> void print_tate(vector<T> &v) {rep(i,v.size()) cout<<v[i]<<"\n";}
void yneos(bool a){if(a) cout<<"Yes"<<"\n"; else cout<<"No"<<"\n";}

ll f(ll l,ll r){
	ll ans=(l+r)%Q;
	ans=(ans*(r-l+1))%Q;
	ans*=(Q/2+1);
	return ans%Q;
}

ll g(ll a){
	return (((a*(a+3))%Q)*(Q/2+1))%Q;
}

//おちこんだりもしたけれど、私はげんきです。
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	ll n,m;
	cin>>n>>m;
	ll ans=0;
	ll upper=sqrt(n)+4;
	chmin(upper,m);
	for(ll x=1;x<=upper;x++){
		ll y=n/x;
		ans+=(x*g(y))%Q;
		ans%=Q;
		//cout<<ans<<endl;
	}
	//cout<<ans<<endl;
	upper++;
	ll now=n/upper;
	ll n_upper;
	//cout<<upper<<endl;
	while(upper<=m){
		if(now==0) n_upper=m;
		else n_upper=n/now;
		chmin(n_upper,m);
		ans+=(g(now)*f(upper,n_upper))%Q;
		ans%=Q;
		upper=n_upper+1;
		now--;
	}
	cout<<ans<<"\n";
	return 0;
}