Error while doing HTTP request android

I'm implementing a native android app that requests with a WS. When trying to make the connection in method connect() of HttpURLConnection I'm getting an error that does not fall into catch to be validated.

Doing some research, I discovered that the error is due to the port that I reported in my connection URL because my server is local. I have set the door number 80886 for example. With this I received the error java.lang.IllegalArgumentException: port=80886 . Searching a little more I understood that the maximum number of ports accepted is of 65535 and in fact if I put the 65536 port I get the same error mentioned previously, a smaller port does not of the problems.

So far this is understandable since I have seen that it has a connection with the TCP protocols, and that magic number 65535 is actually the maximum number since it is the calculation of 2 ^ 16. Because the port handles are 16-bit integers, this is the maximum value that is accepted.

I took the test using 2 different devices. One with android version 4.4.4 and another with version 8.0.0. In the device with version 4.4.4 the error occurred, already in android 8.0.0 I had no problems.

Could you explain why this happened? Why does an error occur only in the old version?

Method Code:

public static boolean testarConexaoServidor(String url) {

    boolean retorno = false;
    int milissegundos = 20000;

    try {
        URL apiEnd = new URL(url);
        int codigoResposta;
        HttpURLConnection conexao;

        conexao = (HttpURLConnection) apiEnd.openConnection();
        conexao.setRequestMethod("GET");
        conexao.setReadTimeout(milissegundos);
        conexao.setConnectTimeout(milissegundos);
        conexao.connect();

        codigoResposta = conexao.getResponseCode();
        if (codigoResposta < HttpURLConnection.HTTP_BAD_REQUEST) {
            retorno = true;         
        }

        conexao.disconnect();


    } catch (MalformedURLException e) {
        e.printStackTrace();

    } catch (IOException e) {
        e.printStackTrace();
    }

    return retorno;
}