81525 has 12 divisors (see below), whose sum is σ = 134912. Its totient is φ = 43440.

The previous prime is 81517. The next prime is 81527. The reversal of 81525 is 52518.

It is not a de Polignac number, because 81525 - 2³ = 81517 is a prime.

It is a Duffinian number.

81525 is a lucky number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 81525.

It is not an unprimeable number, because it can be changed into a prime (81527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 469 + ... + 618.

2⁸¹⁵²⁵ is an apocalyptic number.

It is an amenable number.

81525 is a deficient number, since it is larger than the sum of its proper divisors (53387).

81525 is a wasteful number, since it uses less digits than its factorization.

81525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1100 (or 1095 counting only the distinct ones).

The product of its digits is 400, while the sum is 21.

The square root of 81525 is about 285.5258307054. The cubic root of 81525 is about 43.3607650110.

It can be divided in two parts, 81 and 525, that added together give a palindrome (606).

The spelling of 81525 in words is "eighty-one thousand, five hundred twenty-five".