#include <fstream>
using namespace std;
ifstream fin ("fact.in");
ofstream fout ("fact.out");
int main()
{
    unsigned long long int p,n=0,nrz=0,copyn;
    fin >> p;
    while (nrz<p)
    {
        n+=25;
        copyn=n;
        while (copyn%5==0 && copyn!=0)
        {
            copyn-=5;
            nrz++;
        }
        while (nrz>p)
        {
            n-=5;
            nrz--;
        }
    }
    if (nrz==p && p!=0)
    {
        fout << n;
    }
    else if (p==0)
    {
        fout << 1;
    }
    else fout << -1;
    return 0;
}