None. They are all just letters.
7 have rot
Eleven of them - AHIMOTUVWXY
Seven
It really depends on how you write the letters. I count nine if there're all uppercase, but that's my handwriting.
If you mean horizontally asymmetrical there are 15: BCDEFGJKLNPQRSZ If you mean vertically asymmetrical there are 17: AFGJLMNPQRSTUVWYZ
There are seven: B, H, I, O, S, X, Z
26 x 25 x 24 = 15600
the alphabet has 26 letters in it
The official Philippine alphabet has 28 letters.
There were 22 letters in the Phoenician alphabet.
The English language alphabet has 26 letters.
The Somali Latin alphabet has 32 letters. The Somali Osmanya alphabet has 22 letters.