#include<iostream>
#include<algorithm>
#include<math.h>
#include<stdio.h>
#define SIZE 100

using namespace std;

long long n;
int len = 0, a[SIZE];

int main()
{
	freopen("input.txt","r",stdin);
	freopen("output.txt","w",stdout);

	cin >> n;

	if(n == 1)
	{
		cout << "1\n";
		return 0;
	}

	if(n == 0)
	{
		cout << "10\n";
		return 0;
	}

	for(int i = 9; i > 1; i--)
		while(n%i == 0)
		{
			n /= i;
			a[len] = i;
			len++;
		}

	if(n != 1)
	{
		cout << "-1\n";
		return 0;
	}

	while(len > 0)
	{
		len--;
		cout << a[len];
	}

	return 0;
}