99999...22131 (48-digits)

This number is a prime.

                        99999999 9777777755 5553331888 8888866666 6444422131

The only almost pandigital prime concatenated in descending order from the odd digits followed from the concatenation of the even digits also in descending order using d times each digit d and ending with a 3-digit palindromic prime. [Loungrides]