from functools import cmp_to_key
def cmp(a, b):
    x, y = a[0], a[1] - 1
    xx, yy = b[0], b[1] - 1
    s = x * yy - y * xx
    return 1 if s > 0 else -1 if s < 0 else 0

cmpkey = cmp_to_key(cmp)

P = 10 ** 9 + 7
N = int(input())
X = sorted([(int(a), int(b)) for a, b in zip(input().split(), input().split())], key = cmpkey)
ans = 0
l = 1
for a, b in X:
    ans = (ans + l * a) % P
    l = l * b % P
print(ans)