27469 is a product of two 4k+1 primes and so it can be expressed as a sum of two squares in two different ways viz. 30^2+163^2 and 35^2+162^2.

27469 is a member of OEIS A152852: numbers with all different digits s.t. each digit leaves the same nonzero remainder when each is divided into the number, here 1.

The sequence can be generated as follows:

INPUT

L=[]

for n in [10..40000]:

  D=n.digits()

  if len(D)==len(Set(D)) and 0 not in D:

    E=[]

    for d in D:

      rem=n%d

      E.append(rem)

    if len(Set(E))==1 and 0 not in E:

      L.append(n)

print(L)

OUTPUT

[289, 379, 386, 469, 649, 673, 674, 869, 938, 2437, 4873, 23689, 24697, 27469, 28369, 32689, 36289, 36794]

27471 is a semiprime whose concatenation of prime factors (from lower to higher AND from higher to lower) is a prime, here 1321113 and 211313.

27469 is a cyclic, Duffinian and lucky number

27469 cannot seemingly be rendered as a digit equation using simple arithmetic operations: *NO_EQUATION*