89999...32213 (47-digits)

This number is a prime.

                         8999999 9998888888 8777777766 6666555554 4443332213

The larger of only two primes formed by inserting between the digits of a double-digit prime, i.e., 83, the concatenation in reverse order of all the rep-digit numbers made up by using d times each digit d. [Loungrides]