#include<fstream>
using namespace std;
long long i,p,n,nr,x;
long long fact(long long p)
{long long i,x=0,nr=0,n=0;
    for(i=5;i<=p*5;i=i+5)
{x=i;
    while(x%5==0)
{nr++;
x=x/5;
}
if(nr==p)
    n=i;
}
    return n;
}
int main()
{ifstream f("fact.in");
ofstream g("fact.out");
f>>p;
if(p==0)
g<<"1";
else
{
if(fact(p)==0)
g<<"-1";
else
g<<fact(p);
}
return 0;
}