81535 has 8 divisors (see below), whose sum is σ = 102240. Its totient is φ = 62304.

The previous prime is 81533. The next prime is 81547. The reversal of 81535 is 53518.

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 81535 - 2¹ = 81533 is a prime.

It is a super-3 number, since 3×81535³ = 1626123332416125, which contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 240 + ... + 469.

It is an arithmetic number, because the mean of its divisors is an integer number (12780).

2⁸¹⁵³⁵ is an apocalyptic number.

81535 is a deficient number, since it is larger than the sum of its proper divisors (20705).

81535 is a wasteful number, since it uses less digits than its factorization.

81535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 737.

The product of its digits is 600, while the sum is 22.

The square root of 81535 is about 285.5433417189. The cubic root of 81535 is about 43.3625378411.

It can be divided in two parts, 81 and 535, that added together give a palindrome (616).

The spelling of 81535 in words is "eighty-one thousand, five hundred thirty-five".