#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef pair<ll,ll> P;
typedef vector<ll> VI;
typedef vector<VI> VVI;
#define REP(i,n) for(ll i=0;i<(n);i++)
#define ALL(v) v.begin(),v.end()
template<typename T> bool chmax(T &x, const T &y) {return (x<y)?(x=y,true):false;};
template<typename T> bool chmin(T &x, const T &y) {return (x>y)?(x=y,true):false;};
constexpr ll MOD=1000000007;
constexpr ll INF=2e18;

bool comp(P& l, P& r){
    return l.first*r.second < l.second*r.first;
}

int main(){
    int n; cin >> n;
    VI a(n), b(n);
    REP(i,n) cin >> a[i];
    REP(i,n) cin >> b[i];
    vector<P> p(n);
    REP(i,n) p[i]={a[i],b[i]-1};
    sort(ALL(p),comp);
    ll ans=0, x=1;
    REP(i,n){
        //cout << p[i].first << " " << p[i].second << endl;
        ans=(ans+x*p[i].first%MOD)%MOD;
        x=(x*(p[i].second+1))%MOD;
    }
    cout << ans << endl;
}