27529 is a 4k+1 prime and so it can be expressed as a sum of two squares in one way only viz. 148^2 + 75^2.
27529 is a member of OEIS A358744: first of three consecutive primes p, q, r such that p + q - r, p^2 + q^2 - r^2 and p^3 + q^3 - r^3 are all prime.
The sequence can be generated as follows (permalink):
INPUT
L=[]
for p in prime_range(40000):
q=next_prime(p)
r=next_prime(q)
if is_prime(p+q-r):
if is_prime(p^2+q^2-r^2):
if is_prime(p^3+q^3-r^3):
L.append(p)
print(L)
OUTPUT
[13, 29, 137, 521, 577, 691, 823, 1879, 3469, 4799, 8783, 21569, 25453, 26263, 26591, 27529, 27919, 34607, 39509]
27529 cannot be rendered as a digit equation:
*NO_EQUATION*