class Eratosthenes:
    def __init__(self, n):
        self.isPrime = [True]*(n+1)
        self.isPrime[0], self.isPrime[1] = False, False
        self.mobius = [1]*(n+1)
        for i in range(2, n+1):
            if self.isPrime[i]:
                self.mobius[i] = -1
                for j in range(i*2, n+1, i):
                    self.isPrime[j] = False
                    if j//i%i == 0:
                        self.mobius[j] = 0
                    else:
                        self.mobius[j] *= -1

MOD = 998244353

half = pow(2, -1, MOD)
def rangeSUM(l, r, c):
    return (l+r)%MOD*c%MOD*half%MOD

N, M = map(int, input().split())

MIN = min(N, M)

E = Eratosthenes(MIN)
ans = 0
for n in range(1, MIN+1):
    ans += rangeSUM(n, N//n*n, N//n)*rangeSUM(n, M//n*n, M//n)%MOD*E.mobius[n]
    ans %= MOD

print(ans)