mod = 1000000007 def main(): import sys input = sys.stdin.readline from functools import cmp_to_key def cmp_func(X, Y): xy0 = X[0] + Y[0] * X[1] xy1 = Y[0] + X[0] * Y[1] if xy0 == xy1: return 0 elif xy0 > xy1: return -1 else: return 1 N = int(input()) A = list(map(int, input().split())) B = list(map(int, input().split())) AB = [(a, b) for a, b in zip(A, B)] AB.sort(key=cmp_to_key(cmp_func)) ans = 0 x = 1 for a, b in AB: ans = (ans + (a * x) % mod)%mod x = (x * b)%mod print(ans % mod) if __name__ == '__main__': main()