#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
using ll=long long;
#define rep(i,n) for(int i=0;i<n;i++)
#define rrep(i,n) for(int i=(n)-1;i>=0;i--)
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
template<class T> bool chmax(T &a, T b){if (a < b){a = b;return true;} else return false;}
template<class T> bool chmin(T &a, T b){if (a > b){a = b;return true;} else return false;}

const ll MOD=1e9+7;

bool compare(pair<ll,ll> &p1,pair<ll,ll> &p2){
    return p2.first+p1.first*p2.second>p1.first+p1.second*p2.first;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int N;
    cin>>N;
    vector<ll>A(N),B(N);
    rep(i,N)cin>>A[i];
    rep(i,N)cin>>B[i];
    vector<pair<ll,ll>>vp;
    rep(i,N)vp.push_back(make_pair(A[i],B[i]));
    sort(all(vp),compare);
    ll ans=0;
    for(auto[a,b]:vp)ans=(a+b*ans)%MOD;
    cout<<ans<<"\n";
}