where n is the number of letters in the word and nk represents the number of repetitions of a letter in the word. For example, the number of anagrams for the word "rearrange" is 9!3!2!2!1!1! as there are 9 letters in the word with 'r' repeated 3 times, 'e' and 'a' repeated twice each, and 'n' and 'g' only used once.Jul 23, 2014