27605 is a product of two 4k+1 primes and so it can be expressed as a sum of two squares in two ways viz. 7^2 + 166^2 and 94^2 + 137^2.

27605 is a member of OEIS A002858: Ulam numbers, here 27605 = 69 + 27536.

27605 is a number that requires 31 steps to reach a home prime, here 37113338057626611049460932254446827756425172690469526888619.

27605 is a xenodrome in bases 10, 12, 13, 15 and 16.

27605 is a Duffinian number.

27605 can be rendered as a digit equation as follows:

-2 + 7 * 6 ^ 0 = 5