81579 has 8 divisors (see below), whose sum is σ = 110592. Its totient is φ = 53480.

The previous prime is 81569. The next prime is 81611. The reversal of 81579 is 97518.

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 81579 - 2⁴ = 81563 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81509) 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, 22 + ... + 404.

It is an arithmetic number, because the mean of its divisors is an integer number (13824).

2⁸¹⁵⁷⁹ is an apocalyptic number.

81579 is a deficient number, since it is larger than the sum of its proper divisors (29013).

81579 is a wasteful number, since it uses less digits than its factorization.

81579 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 457.

The product of its digits is 2520, while the sum is 30.

The square root of 81579 is about 285.6203774243. The cubic root of 81579 is about 43.3703365720.

The spelling of 81579 in words is "eighty-one thousand, five hundred seventy-nine".