Yes, it is a phone number. NUK are the letters associated with numbers. If you look at a phone with English letters, you'll see ABC on the number 2 button, DEF on the number 3 button and so on. N is on the 6 key, U is on the 8 key, K is on the 5 key. So 1-888-NUK-1238 = 1-888-685-1238 This is a way for people to associate words with phone numbers for advertising or for fun.