import bisect
import copy
import decimal
import fractions
import heapq
import itertools
import math
import random
import sys
import time
from collections import Counter,deque,defaultdict
from functools import lru_cache,reduce
from heapq import heappush,heappop,heapify,heappushpop,_heappop_max,_heapify_max
def _heappush_max(heap,item):
    heap.append(item)
    heapq._siftdown_max(heap, 0, len(heap)-1)
def _heappushpop_max(heap, item):
    if heap and item < heap[0]:
        item, heap[0] = heap[0], item
        heapq._siftup_max(heap, 0)
    return item
from math import gcd as GCD
read=sys.stdin.read
readline=sys.stdin.readline
readlines=sys.stdin.readlines

N=int(readline())
A=list(map(int,readline().split()))
B=list(map(int,readline().split()))
class idx:
    def __init__(self,i):
        self.i=i
    def __lt__(self,other):
        i=self.i
        j=other.i
        return A[i]+A[j]*B[i]<A[j]+A[i]*B[j]
ans=0
x=1
mod=10**9+7
lst=[idx(i) for i in range(N)]
lst.sort(reverse=True)
for id in lst:
    i=id.i
    ans+=A[i]*x
    x*=B[i]
    ans%=mod
    x%=mod

print(ans)