#include <fstream>
#include<iostream>
using namespace std;
int main()
{
    ifstream in;in.open("fact.in");
    ofstream ou;ou.open("fact.out",ofstream::out);
    long n,i,q,j;
    q=0;
    in>>n;
    if(n==0)ou<<1;
    else
    for(i=5;;i+=5)
        {
            q++;j=i;
            if(j%125==0){j/=125;q+=2;}
        if(j%25==0)while(j%25==0){j/=5;q++;if(q>n)break;}
        if(q==n){ou<<i;break;}
        else if(q>n){ou<<-1;break;}
        }
    in.close();ou.close();
    return 0;
}