#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using ll=long long;
using mint=atcoder::modint998244353;
int main(){
	ll n,m;
	cin>>n>>m;
	set<ll> quo;
	ll sr=sqrtl(m);
	for(ll i=1;i<=sr;i++) quo.insert(m/i),quo.insert(i);
	vector<ll> qs(quo.begin(),quo.end());
	mint ans=m,inv2=mint(2).inv();
	ans*=n;
	for(ll i=0;i<qs.size()-1;i++){
		ll l=m/qs[i+1]+1,r=m/qs[i];
		if(l>n) continue;
		ans-=mint(qs[i])*mint(min(r,n)-l+1)*mint(min(r,n)+l)*inv2;
	}
	ans-=m;
	cout<<ans.val()<<endl;
}