This number is a prime.
28657 is the smallest prime, which is a Fibonacci number (F(23)prime) and an anagram of a triangular number (67528 = T(367)prime). [Meller]
The only five-digit prime Fibonacci number. [Undis]
The largest distinct-digit Fibonacci prime. Note that the sum of its digits is a perfect number, as well as its first 2-digit string. [Loungrides]