#include <fstream>

using namespace std;
ifstream fin("fact.in");
ofstream fout("fact.out");
int main()
{
    int n,x,p;
    long long pas;
    fin>>p;
    if(p==0) fout<<1;
    else if(p==1) fout<<5;
    else if(p==2) fout<<10;
    else
    {
        n=2;
        pas=10;
        for(;;)
        {
            pas+=5;
            x=pas;
            while(x%5==0) x/=5,n++;
            if(n>p) {fout<<-1;;break;}
            else if(n==p) {fout<<pas;break;}
        }
    }
}