27557 is a product of two 4k+1 primes and can therefore be expressed as a sum of two squares in two different ways viz. 1^2+166^2 and 79^2+146^2.

27557 is number n such that n plus digit sum of n and n-1 plus digit sum of n-1 are both prime. Here we have:

27556 + 25 = 27581 which is prime

27557 + 26 = 27583 which is prime

27557 is a cyclic, Duffinian and Cunningham number.

27557 cannot be rendered as a digit equation as far as can be determined: *NO_EQUATION*