According to ur question... vowels can only interchange places with vowels, and consonants can only interchange places with consonants .....
Consider Consonants ----
6! / 2! 2!
6! because there are 6 letters excluding the vowels.
2! because T is repeated twice
another 2! because P is repeated twice
Now consider vowels ----
4! / 2!
4 vowels, and A repeated 2 times
So total number of words that can be formed are :
= (6! / 2! 2!). (4! / 2!)
= 6! . 3
= 2160 words