Why mail not send from my localhost php 7 in codeigniter - email

Question

From my localhost, i cannot send email using gmail account. I've Used php 7.0.9 and codeigniter. I wrote the code in controller is-
$this->load->library('email');
$config['protocol'] = 'smtp';
$config['smtp_host'] = 'ssl://smtp.googlemail.com';
$config['smtp_port'] = '25';
$config['smtp_user'] = 'xxx#gmail.com';
$config['smtp_pass'] = 'password';
$config['charset'] = 'utf-8';
$config['newline'] = "\r\n";
$config['mailtype'] = 'html';
$config['wordwrap'] = TRUE;
$this->email->initialize($config);
$this->email->from('xxx#gmail.com');
$this->email->to('aaaa#yahoo.com');
$this->email->subject("Welcome to xx.");
$this->email->message('message body.....');
if ($this->email->send()) {
$data['success'] = 1;
} else {
$data['success'] = 0;
$data['error'] = $this->email->print_debugger(array('headers'));
}
echo "<pre>";
print_r($data);
echo "</pre>";
But I got the error
Array
(
[success] => 0
[error] => The following SMTP error was encountered: 0
Unable to send data: AUTH LOGIN
Failed to send AUTH LOGIN command. Error:
Unable to send data: MAIL FROM:
from:
The following SMTP error was encountered:
Unable to send data: RCPT TO:
to:
The following SMTP error was encountered:
Unable to send data: DATA
data:
The following SMTP error was encountered:
Unable to send data: User-Agent: CodeIgniter
Date: Wed, 26 Oct 2016 12:10:08 +0200
Anyone please give me suggestion about it.