Number keys not working
The setting of Mouse Keys could have been activated while syncing from a MobileMe account that had the preference enabled, migrating a user from another computer using Migration Assistant that had the preference enabled, or by pressing the Option key five times (if that setting is enabled in System Preferences).

To check your System Preference settings, or to enable/disable Mouse Keys:


Open System Preferences and click on the Universal Access preference pane. 
Click the Mouse &amp; Trackpad settings tab. 
Click the "Off" radio button next to Mouse Keys.


Note1: You may also check/uncheck the box for "Press Option key five times to turn Mouse Keys on or off". 

Note2: If you are logged on to a user where Mouse Keys is already disabled, but your keyboard is not responding properly, toggle the radio buttons for Mouse Keys "On" then "Off" to restore normal functionality.