#include<iostream.h>
#include<stdio.h>
int main ()
{int N,n=0,N2,truth=-1;
long int P;
freopen ("fact.in", "rt" ,stdin);
freopen ("fact.out","wt" ,stdout);
scanf("%ld",&P);
if (P==0) N=6;
else for (N=5;n<P;N=N+5) {N2=N;
		          while (N2%5==0) {N2=N2/5;
				           n++;}}
      if (n>P) cout <<truth;
      if (n==P) printf("%d",N-5);
return 0;}