def sieves(nn: int):
    is_prime = [True] * nn
    least_p = [-1] * nn
    is_prime[0] = is_prime[1] = False
    least_p[1] = 1
    mobius = [1] * nn
    mobius[0] = 0
    for p in range(2, nn):
        if not is_prime[p]:
            continue
        least_p[p] = p
        mobius[p] = -1
        for q in range(p * 2, nn, p):
            is_prime[q] = False
            if least_p[q] == -1:
                least_p[q] = p
            if q % (p * p) == 0:
                mobius[q] = 0
            else:
                mobius[q] *= -1
    primes = [p for p in range(2, nn) if is_prime[p]]
    return is_prime, least_p, primes, mobius

def prime_factorize(n: int):
    ans = {}
    while n > 1:
        p = least_p[n]
        e = 0
        while n % p == 0:
            n //= p
            e += 1
        ans[p] = e
    return ans

def get_divisors(n: int):
    """正の約数列挙

    Args:
        n (int): 約数を求める数 (>= 1)

    Returns:
        list[int]: `n`の正の約数

    Notes:
        - `n`の約数の個数をσ(n)として
        - 計算量 Θ( σ(n) * log(σ(n)) )
        - n <= 10^7 で σ(n) <= σ(8648640) = 448
        - n <= 10^9 で σ(n) <= σ(735134400) = 1344
        - n <= 10^18 で σ(n) <= σ(897612484786617600) = 103680
    """
    pe = prime_factorize(n)
    ans = [1]
    for p, e in pe.items():
        exps = [p ** ei for ei in range(1, e + 1)]
        ans.extend([d * f for d in ans for f in exps])
    ans.sort()
    return ans

is_prime, least_p, primes, mobius = sieves(10**5 + 100)
from collections import defaultdict
n, k = map(lambda s_: int(s_), input().split())
a = tuple(map(lambda s_: int(s_), input().split()))
b = tuple(map(lambda s_: int(s_), input().split()))
cost = [[] for _ in range(n)]
for i in range(n):
    ai, bi = a[i], b[i]
    ci = cost[i]
    ds = get_divisors(ai)
    dcd = defaultdict(int)
    for d in ds:
        dcd[(bi + d - 1) // d * d - bi] = d
    for c, d in sorted(dcd.items()):
        if ci and ci[-1][0] > d:
            continue
        else:
            ci.append((d, c))

import bisect
# for ci in cost:
#     print(ci)
def check(g):
    ans = 0
    for ci in cost:
        ok = len(ci)
        ng = -1
        while abs(ok - ng) > 1:
            mi = (ok + ng) // 2
            if ci[mi][0] >= g:
                ok = mi
            else:
                ng = mi
        # i = bisect.bisect_left(ci, (g, 0))
        i = ok
        if i == len(ci):
            # print(">>", ci, g, i)
            return False
        ans += ci[i][1]
    # print(">", g, ": ", ans)
    return ans <= k
ok = 0
ng = min(a) + 1
while abs(ok - ng) > 1:
    mi = (ok + ng) // 2
    if check(mi):
        ok = mi
    else:
        ng = mi
print(ok)
# for i in range(1, 10):
#     print(check(i))