Mmm, yes, you'd never see "are not I" or "are I not" written down, but you might see "am not I" or even better "am I not". It really should be "amn't", wonder how it got to be "aren't"?
(edit)
D'oh, I'm an idiot, forget the rubbish that was in this place earlier.
I forget the existence of "I'm".
This then is my second attempt:
We can say:
I am
He/She/It is
You/They/We are
I'm
He/She/It's
You/They/We're
and we can say:
I am not
He/She/It is not
You/They/We are not
I'm not - different words being contracted, though!
He/She/It isn't
You/They/We aren't
But only:
Am I not?
Isn't He/She/It?
Aren't You/They/We?
There's a gap where amn't should go which we fill for some reason with "aren't". 
_________________
No one has gone missing or died.
The year is still young.