Palindromic and Tautonymic IV (Posted on 2010-12-27)

Make a list of distinct positive integers that are obtained by assigning a different decimal digit from 1 to 9 to each of the capital letters in bold in this expression.

(A+B)^{C} + (D+E)^{F} + (G+H)^{I}

Determine the smallest and the largest positive palindromes. What are the smallest and the largest prime number? How many amongst the abovementioned list are tautonymic numbers?