#include<stdio.h>


int main()
{

    FILE *in, *out;   
    register int n, p, c5, man;
    
    in=fopen("fact.in", "r");
    out=fopen("fact.out", "w");
    
    fscanf(in, "%d", &p);
    c5=0; n=5;
    
    if (p==0) 
    {
        fprintf(out, "1"); return 0;
    }
    
    while (c5<p)
    {
        man=n;
        while (man%5==0)
        {   c5++;
            if (c5>p) 
            {
                fprintf(out, "-1"); return 0;
            }
            man/=5;
        }
        n+=5;
    }
    
    fprintf(out, "%d", n-5);
    
    return 0;
}