n = int(input())
A = list(map(int, input().split()))
B = list(map(int, input().split()))
AB = []
AB1 = []
for i in range(n):
    if B[i] == 1:
        AB1.append((A[i], B[i]))
    else:
        AB.append((A[i], B[i]))

AB.sort(key=lambda x: x[0] / (x[1] - 1))
mod = 10**9 + 7
ans = 0
curr = 1
for a, b in AB:
    ans += curr * a % mod
    ans %= mod
    curr *= b
    curr %= mod
for a, _ in AB1:
    ans += curr * a % mod
    ans %= mod
print(ans)