Possible to Permanently Delete or Deactivate Acct?

For personal reasons, I would like to stop playing here and cancel my account.  Is this possible in a way that would delete my account entirely or deactivate it completely and not allow me (or any "hackers") to ever use my account again?

Appreciate the feedback.

 You can close your account. Go to settings and you can find the option there below your account information.

This is true, but the account will still be shown but just marked as "Closed: Inactive". You will probably need to contact support to see if they are willing to permanently wipe your data. (Possibly they will be required to do this for EU residents once GDPR takes effect.)

Ah yes, that's right the closed account still appears. It is better to contact support so they can do something about this closed accounts players.