#include <iostream>
#include <cmath>

using namespace std;

long tw (int o, long x)
{
   long sum = 0, i = 0;
   while (x >= 1) {
        sum += x % o;
        x = x / o;
   }
   return sum;
}

int main()
{
    int n, key = 0, code = 0;
    cin >> n;
    long numb;
    for (long i = 4; i < 1000000000; i++) {
        long sum = 0, dsum = 0, p = 0;
        sum = tw (n, i);
        long j = i;
        while (j > 1) {
            for (long k = 2; k <= j; k++) {
                if (j % k == 0) {
                    p ++;
                    dsum += tw (n, k);
                    j /= k;
                    if (j % k == 0) {
                        k--;
                    }
                }
            }
        }
        if ((sum == dsum) && (p != 1)) {
            key++;
        } else {
            key = 0;
        }
        if (key == 2) {
            code ++;
        }
        if ((code == 2) || (key == 3)) {
            numb = i - 1;
            break;
        }
    }
    cout << numb;
    return 0;
}