N, M = map(int, input().split())
if N > M:
	N, M = M, N

lp = [-1] * (N + 1)
f = [1] * (N + 1)
for i in range(2, N + 1):
	if lp[i] == -1:
		for j in range(i, N + 1, i):
			lp[j] = i
	f[i] = f[i // lp[i]] * (1 - lp[i] if i % (lp[i] * lp[i]) else 1)

MOD = 998244353
ans = 0
for d in range(1, N + 1):
	x, y = N // d, M // d
	ans += ((f[d] + MOD) * d * x * (x + 1) * y * (y + 1) // 4) % MOD
print(ans % MOD)