#include<stdio.h>
int a,i,n,aux,b,k=0;
long long nr=5;
int main()
{
	freopen("fact.in","r",stdin);
	freopen("fact.out","w",stdout);
	scanf("%d",&a);
n=0;
	while(n<=a)
	     {aux=nr;
	      b=0;
			 while(aux%5==0)
		       {b++;
				aux/=5;
			    }
          n+=b;
		  if(n==a)
			  {printf("%d",nr);
		       k=1;
			   }
          nr+=5;		  
		  }
if(k!=1)
printf("-1");	

return 0;}