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

int main() {
    long long N, M;
    cin >> N >> M;

    mint ret = mint(M) * mint(N);

    for (long long k = 1; k <= N;) {
        long long d = M / k;
        if (d == 0) break;
        long long kr = min(M / d, N);

        long long n = kr - k + 1;

        ret -= mint(d) * n * (k + kr) / 2;

        k = kr + 1;
    }

    cout << ret.val() << '\n';
}