8209

This number is a prime.

8209^3 = 553185473329, and 5^2 + 5^2 + 3^2 + 1^2 + 85^2 + 4^2 + 7^2 + 3^2 + 3^2 + 29^2 = 8209. [Meller]

The smallest prime adjacent to a multidigit narcissistic number, i.e., 8208. [Loungrides]