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

using ll = long long;
constexpr ll mod = 998244353;

int main() {
	int N, M;
	cin >> N >> M;
	if(N > M) swap(N, M);
	
	vector<int> lp(N + 1, -1), mu(N + 1, 1);
	for(int i = 2; i <= N; ++i) {
		if(lp[i] == -1) for(int j = i; j <= N; j += i) lp[j] = i;
		mu[i] = (i % (lp[i] * lp[i]) == 0 ? 0 : mu[i / lp[i]] * -1);
	}
	
	vector<int> f(N + 1, 0);
	for(int i = 1; i <= N; ++i) for(int j = i; j <= N; j += i) f[j] += i * mu[i];
	
	ll ans = 0;
	for(ll n = 1; n <= N; ++n) {
		const ll x = N / n, y = M / n;
		ans = (ans + n * (f[n] + mod) % mod * (x * (x + 1) / 2 % mod) % mod * (y * (y + 1) / 2 % mod) % mod) % mod;
	}
	
	cout << ans << "\n";
}