81529 has 8 divisors (see below), whose sum is σ = 98240. Its totient is φ = 66096.

The previous prime is 81527. The next prime is 81533. The reversal of 81529 is 92518.

81529 is nontrivially palindromic in base 6.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81529 - 2¹ = 81527 is a prime.

It is a Duffinian number.

81529 is a lucky number.

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 7 ways as a sum of consecutive naturals, for example, 174 + ... + 439.

It is an arithmetic number, because the mean of its divisors is an integer number (12280).

2⁸¹⁵²⁹ is an apocalyptic number.

It is an amenable number.

81529 is a deficient number, since it is larger than the sum of its proper divisors (16711).

81529 is a wasteful number, since it uses less digits than its factorization.

81529 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 639.

The product of its digits is 720, while the sum is 25.

The square root of 81529 is about 285.5328352397. The cubic root of 81529 is about 43.3614741605.

It can be divided in two parts, 81 and 529, that multiplied together give a square (42849 = 207²).

The spelling of 81529 in words is "eighty-one thousand, five hundred twenty-nine".