#ifdef NACHIA
#define _GLIBCXX_DEBUG
#else
#define NDEBUG
#endif
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using i64 = long long;
using u64 = unsigned long long;
#define rep(i,n) for(int i=0; i<int(n); i++)
const i64 INF = 1001001001001001001;
template<typename A> void chmin(A& l, const A& r){ if(r < l) l = r; }
template<typename A> void chmax(A& l, const A& r){ if(l < r) l = r; }
#include <atcoder/modint>

namespace nachia{

template<class Int = long long>
std::vector<Int> EnumerateQuotients(Int N, bool doInsertZero){
    std::vector<Int> res;
    if(doInsertZero) res.push_back(0);
    Int f = 1;
    for( ; f*f<N; f++) res.push_back(f);
    int qp1 = res.size();
    for(Int k=1; k*f<=N; k++){
        res.push_back((k&1) ? (N/k) : (res[qp1+k/2-1]/2));
    }
    std::reverse(res.begin() + qp1, res.end());
    return res;
}

}
using Modint = atcoder::static_modint<998244353>;
using namespace std;

void testcase(){
    i64 N, M; cin >> N >> M;
    Modint ans = Modint(M) * Modint(N);
    auto q = nachia::EnumerateQuotients(M, true);
    Modint inv2 = Modint(2).inv();
    rep(i,q.size()-1){
        i64 l = min(N, q[i]);
        i64 r = min(N, q[i+1]);
        i64 f = q[q.size() - 1 - i];
        Modint d = 0;
        d += Modint(r) * Modint(r+1) * inv2;
        d -= Modint(l) * Modint(l+1) * inv2;
        d *= f;
        ans -= d;
    }
    cout << ans.val() << endl;
}

int main(){
    ios::sync_with_stdio(false); cin.tie(nullptr);
    testcase();
    return 0;
}