You can change your password, security question, and enable/disable 2-step verification.
2-step verification provides an extra layer of security to protect your sensitive data. When you enable this feature, you will be asked to associate a mobile phone number. This mobile will be needed each time you log in. When you have entered your password, you will be sent a code via text message to the phone associated with the 2-step verification. You can change your mobile number or disable this feature at any time.
When changing your password, note that it must be at least 8 characters long and contain at least 1 numeric character. The answer to your security question must be at least 8 characters long.