#include <stdio.h>

const int Mod = 1000000007;

typedef struct {
	int key[2], id;
} data;

void merge_sort(int n, data x[])
{
	static data y[200001] = {};
	if (n <= 1) return;
	merge_sort(n / 2, &(x[0]));
	merge_sort((n + 1) / 2, &(x[n/2]));
	
	int i, p, q;
	for (i = 0, p = 0, q = n / 2; i < n; i++) {
		if (p >= n / 2) y[i] = x[q++];
		else if (q >= n) y[i] = x[p++];
		else y[i] = ((long long)x[p].key[0] * x[q].key[1] <= (long long)x[q].key[0] * x[p].key[1])? x[p++]: x[q++];
	}
	for (i = 0; i < n; i++) x[i] = y[i];
}

int main()
{
	int i, N, A[200001], B[200001];
	scanf("%d", &N);
	for (i = 1; i <= N; i++) scanf("%d", &(A[i]));
	for (i = 1; i <= N; i++) scanf("%d", &(B[i]));
	
	data d[200001];
	for (i = 1; i <= N; i++) {
		d[i-1].key[0] = A[i];
		d[i-1].key[1] = B[i] - 1;
		d[i-1].id = i;
	}
	merge_sort(N, d);
	
	long long ans = 0, tmp = 1;
	for (i = 0; i < N; i++) {
		ans += tmp * A[d[i].id];
		tmp = tmp * B[d[i].id] % Mod;
	}
	printf("%lld\n", ans % Mod);
	fflush(stdout);
	return 0;
}