#include <stdio.h>


int pow(int base, int exp)
{
    if (exp == 0) return 1;

    int res = 1;
    if (exp % 2 == 1)
        res *= base;

    int pr = pow(base, exp/2);
    res*=pr*pr;

    return res;
}

int getZeros(int p)
{
    int calc = 5;
    int zeros = 0;
    while (calc <= p)
    {
        zeros  += p/calc;
        calc *= 5;
    }

    return zeros;
}


int main()
{
//    freopen("fact.in", "rt", stdin);
//    freopen("fact.out", "wt", stdout);

    int p;
    scanf("%i", &p); //19 breaks

        int bot = 0, top = 100000000000;//pow(5, p);

        while (bot != top)
        {
            int midpoint = (bot+top)/2;
            if (getZeros(midpoint)>=p)
                top = midpoint;
            else
                bot = midpoint+1;
        }

        printf("%i! is the smallest with at least %i trailing zeroes\n", bot?bot:1, p);
}

//40005! is 166737 digits long with 9999 trailing zeros