This Rest api Java code authenticate to insert lead is working in my dev org But when I try to do the same in production it throws error 400 Can anybody sort it out.

           static final String USERNAME     = "arshadsdeveloper@gmail.com.dev";
           static final String PASSWORD     = "************************";
           static final String LOGINURL     = "https://login.salesforce.com";
           static final String GRANTSERVICE = "/services/oauth2/token?grant_type=password";
           static final String CLIENTID     = "************************";
           static final String CLIENTSECRET = "************************";
           private static String REST_ENDPOINT = "/services/data";
           private static String API_VERSION = "/v35.0";
           private static String baseUri;
           private static Header oauthHeader;
           private static Header prettyPrintHeader = new BasicHeader("X-PrettyPrint", "1");
           private static String leadId ;
           private static String leadFirstName;
           private static String leadLastName;
           private static String leadCompany;

   public static void main(String[] args) {

       HttpClient httpclient = HttpClientBuilder.create().build();

       // Assemble the login request URL
       String loginURL = LOGINURL +
                         GRANTSERVICE +
                         "&client_id=" + CLIENTID +
                         "&client_secret=" + CLIENTSECRET +
                         "&username=" + USERNAME +
                         "&password=" + PASSWORD;

       // Login requests must be POSTs
       HttpPost httpPost = new HttpPost(loginURL);
       HttpResponse response = null;

       try {
           // Execute the login POST request
           response = httpclient.execute(httpPost);
       } catch (ClientProtocolException cpException) {
           cpException.printStackTrace();
       } catch (IOException ioException) {
           ioException.printStackTrace();
       }

       // verify response is HTTP OK
       final int statusCode = response.getStatusLine().getStatusCode();
       if (statusCode != HttpStatus.SC_OK) {
           System.out.println("Error authenticating to Force.com: "+statusCode);
           // Error is in EntityUtils.toString(response.getEntity())
           return;
       }

Any help Appreciated.