import sys
input = sys.stdin.readline

N=int(input())
A=list(map(int,input().split()))
B=list(map(int,input().split()))

mod=10**9+7

X=[(A[i],B[i]) for i in range(N)]
X.sort(key=lambda x:(1-x[1])/x[0])

ANS=0
level=1

for a,b in X:
    ANS+=level*a
    level*=b
    ANS%=mod
    level%=mod

print(ANS)