81479 has 4 divisors (see below), whose sum is σ = 82920. Its totient is φ = 80040.

The previous prime is 81463. The next prime is 81509. The reversal of 81479 is 97418.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81479 - 2⁴ = 81463 is a prime.

It is a Duffinian 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 81479.

It is not an unprimeable number, because it can be changed into a prime (81409) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 632 + ... + 749.

It is an arithmetic number, because the mean of its divisors is an integer number (20730).

2⁸¹⁴⁷⁹ is an apocalyptic number.

81479 is a deficient number, since it is larger than the sum of its proper divisors (1441).

81479 is a wasteful number, since it uses less digits than its factorization.

81479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1440.

The product of its digits is 2016, while the sum is 29.

The square root of 81479 is about 285.4452662070. The cubic root of 81479 is about 43.3526081248.

The spelling of 81479 in words is "eighty-one thousand, four hundred seventy-nine".