#define  _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <algorithm>
#include <utility>
#include <functional>
#include <cstring>
#include <queue>
#include <stack>
#include <math.h>
#include <iterator>
#include <vector>
#include <string>
#include <set>
#include <math.h>
#include <iostream>
#include <random>
#include<map>
#include <iomanip>
#include <time.h>
#include <stdlib.h>
#include <list>
#include <typeinfo>
#include <list>
#include <set>
#include <cassert>
#include<fstream>
#include <unordered_map>
#include <cstdlib>
#include <complex>
#include <cctype>
#include <bitset>
using namespace std;
typedef string::const_iterator State;
#define Ma_PI 3.141592653589793
#define eps 1e-5
#define LONG_INF 1e18
#define GOLD 1.61803398874989484820458
#define MAX_MOD 1000000007LL
#define GYAKU 500000004LL
#define MOD 998244353LL
#define seg_size 262144*4
#define REP(a,b) for(long long a = 0;a < b;++a)
int gcd(int a, int b) {
	if (b == 0) return a;
	return gcd(b, a % b);
}
long long cnter[4000000] = {};
long long wow[4000000] = {};
long long calc(long long start, long long hi) {
	long long kousuu = (start+hi-1) / hi;
	long long ende = start - (kousuu-1LL) * hi;
	long long hoge = ende + start;
	hoge %= MAX_MOD;
	hoge *= kousuu;
	hoge %= MAX_MOD;
	hoge *= GYAKU;
	hoge %= MAX_MOD;
	return hoge;
}
int main(){
	iostream::sync_with_stdio(false);
	cin.tie(0);
	long long h, w;
	cin >> h >> w;
	long long ans = (h - 1) * w + (w - 1) * h;
	ans %= MAX_MOD;
	vector<long long> sosuu;
	vector<pair<long long, long long>> gogo;
	for (long long i = 2; i < max(h,w)+1; ++i) {
		if (wow[i] == 0) {
			sosuu.push_back(i);
			for (int q = 1; i * q <= 3000000; ++q) {
				if (gcd(i, q) == 1) {
					wow[i * q]++;
				}
				else {
					wow[i * q] += 100000;
				}
			}
		}
	}
	for (int i = 2; i < max(h,w)+1; ++i) {
		if (wow[i] < 100000) {
			gogo.push_back(make_pair(i, wow[i]));
		}
	}
	for (long long i = 1; i < h; ++i) {
		cnter[i] = (w - 1LL) * w / 2LL;
		cnter[i] %= MAX_MOD;
	}
	for (int i = 0; i < gogo.size(); ++i) {
		if (gogo[i].first > h||gogo[i].first > w) break;
		long long downing = calc(w - gogo[i].first, gogo[i].first);
		if (gogo[i].second % 2 == 1) {
			downing = MAX_MOD - downing;
		}
		for (int t = 1; gogo[i].first * t < h; ++t) {
			cnter[gogo[i].first * t] += downing;
			cnter[gogo[i].first * t] %= MAX_MOD;
		}
	}
	long long tmp = 0;
	for (long long i = 1; i < h; ++i) {
		tmp += cnter[i] * 2LL * (h - i);
		tmp %= MAX_MOD;
	}
	ans += tmp;
	ans %= MAX_MOD;
	cout << ans<< endl;
	/*
	for (int i = 1; i < h; ++i) {
		for (int q = 1; q < w; ++q) {
			if (gcd(i, q) == 1) {
				ans += 2 * (h - i) * (w - q);
			}
		}
	}
	cout << ans << endl;
	*/
}