N = int(input())
A = list(map(int, input().split()))
B = list(map(int, input().split()))
C = []
for i, (a, b) in enumerate(zip(A, B)):
    C.append([(b-1)/a,i])
C.sort(reverse=True)

res = 0
lev = 1
mod =10**9+7
for i in range(N):
    res += A[C[i][1]]*lev
    res %= mod
    lev *= B[C[i][1]]
    lev %= mod
print(res)