#include <bits/stdc++.h>
using namespace std;
using ll = long long;

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

int main() {

    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    ll N,M;
    cin>>N>>M;
    mint an=mint(M)*mint(N);
    ll d=1;
    while(d<=M){
        ll L=M/d;
        ll R=M/(d+1);
        if(min(N,L)-R>0){
            mint p=min(N,L);
            mint q=R;
            an-=(p*(p+1)-q*(q+1))/mint(2)*mint(d);
        }
        if(R==0)break;
        d=M/R;
    }
    cout<<an.val()<<endl;

}