#include <stdio.h>
#include <stdlib.h>

 
     
    
long long o;
int main()
{
FILE *in, *out;
    in = fopen("fact.in", "r");
    out = fopen("fact.out", "w"); 
 
fscanf(in,"%lld",&o);
 
long long s=0,q=0,i;
if(o!=0)
{
for( i=5;s<=o;i=i+5)
{
q=i;
while(q%5==0)
{
s=s+1;
q=q/5;
}
}
if(s!=o)fprintf(out,"%lld",-1);
else fprintf(out,"%lld",i);
}
else fprintf(out,"%lld",1);
 
return 0;
}