27735 is a member of OEIS A046034: numbers whose digits are all primes. In base 6, all its digits are priime as well: 332223.

In fact, in the range up to 40000, there are only 63 such numbers and they are (permalink):

[2, 3, 5, 23, 32, 33, 35, 525, 527, 537, 555, 557, 572, 573, 575, 735, 737, 752, 753, 755, 773, 777, 3225, 3227, 3237, 3327, 3332, 3333, 3335, 3777, 7223, 7232, 7233, 7235, 7253, 7257, 7322, 7323, 7325, 7755, 7757, 7772, 7773, 7775, 22553, 22557, 22772, 22773, 22775, 23235, 23237, 23252, 23253, 23255, 23325, 23327, 27735, 27737, 27752, 27753, 27755, 27773, 27777]

27735 is an interprime number because it is at equal distance from previous prime (27733) and next prime (27737).

27735 can be rendered as a digit equation as follows:

2 + 7 - 7 = -3 + 5

27735 is a xenodrome in base 9 : 42036.