Need help PHP error

I have a PHP error
here is the error

<div style= A PHP Error was encountered Severity: Warning

Message: number_format() expects parameter 1 to be double, string given

Filename: helpers/number_helper.php

Line Number: 49

Backtrace:

File: /var/www/clients/client23/web61/web/Invoice/application/helpers/number_helper.php
Line: 49
Function: number_format

File: /var/www/clients/client23/web61/web/Invoice/application/modules/settings/views/partial_settings_projects_tasks.php
Line: 37
Function: format_amount

File: /var/www/clients/client23/web61/web/Invoice/application/third_party/MX/Loader.php
Line: 404
Function: include

File: /var/www/clients/client23/web61/web/Invoice/application/third_party/MX/Loader.php
Line: 365
Function: _ci_load

File: /var/www/clients/client23/web61/web/Invoice/application/modules/layout/controllers/Layout.php
Line: 81
Function: view

File: /var/www/clients/client23/web61/web/Invoice/application/modules/settings/views/index.php
Line: 82
Function: load_view

File: /var/www/clients/client23/web61/web/Invoice/application/third_party/MX/Loader.php
Line: 404
Function: include

File: /var/www/clients/client23/web61/web/Invoice/application/third_party/MX/Loader.php
Line: 365
Function: _ci_load

File: /var/www/clients/client23/web61/web/Invoice/application/modules/layout/controllers/Layout.php
Line: 40
Function: view

File: /var/www/clients/client23/web61/web/Invoice/application/modules/settings/controllers/Settings.php
Line: 160
Function: buffer

File: /var/www/clients/client23/web61/web/Invoice/index.php
Line: 327
Function: require_once

">

Also this keeps happening when i want to send an email

SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting