#include <stdio.h>
#include <math.h>


int min(int a,int b)
{
    if (a<b) return a;   
    return b;
}


int main()
{
    FILE *in,*out;
    in=fopen("fact.in","r");
    out=fopen("fact.out","w");
    
    int p,nr2=0,nr5=0,aux1=0,aux2=0,no=-1;
    long long n=1,aux;
    fscanf(in,"%d",&p); 
    while ( min(nr2,nr5) <p )
    {
          aux=n;
          aux1=0; aux2=0;
          while (aux%2==0)
          {
              aux/=2;        
              aux1++;  
          }
          aux=n;
          while (aux%5==0)
          {
              aux/=5;        
              aux2++;  
          }
          n++;
          nr2+=aux1;
          nr5+=aux2;
          printf("%d %d %d\n",nr2,nr5,n);
    }  
    if (min(nr2,nr5)==p)
       fprintf(out,"%lld",n-1);
    else
        fprintf(out,"%d",no);
    //printf("%d  \n",n-1);
    //getchar();
    return 0;
}