import sys,random,bisect
from collections import deque,defaultdict
from heapq import heapify,heappop,heappush
from itertools import permutations
from math import log,gcd

input = lambda :sys.stdin.readline().rstrip()
mi = lambda :map(int,input().split())
li = lambda :list(mi())

"""
ai + bi * aj > aj + bj* ai

aj (bi-1)  > ai (bj-1)
bi-1/ai
"""

N = int(input())
A = li()
B = li()

idx = [i for i in range(N)]
idx.sort(key=lambda i:(B[i]-1)/A[i],reverse=True)

x = 1
res = 0
mod = 10**9 + 7
for i in idx:
    a,b = A[i],B[i]
    res += a * x % mod
    res %= mod
    x = x * b % mod

print(res)