#include <bits/stdc++.h>
using namespace std;

#ifdef _RUTHEN
#include "debug.hpp"
#else
#define show(...) true
#endif

using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); i++)
template <class T> using V = vector<T>;

#include <atcoder/modint>
using mint = atcoder::modint1000000007;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int N;
    cin >> N;
    V<pair<ll, ll>> AB(N);
    rep(i, N) cin >> AB[i].first;
    rep(i, N) cin >> AB[i].second;
    sort(AB.begin(), AB.end(), [](pair<ll, ll> x, pair<ll, ll> y) { return x.first + x.second * y.first > y.first + y.second * x.first; });
    show(AB);
    mint ans = 0, cur = 1;
    rep(i, N) {
        ans += cur * AB[i].first;
        cur *= AB[i].second;
    }
    cout << ans.val() << '\n';
    return 0;
}