82391 has 4 divisors (see below), whose sum is σ = 84192. Its totient is φ = 80592.

The previous prime is 82387. The next prime is 82393. The reversal of 82391 is 19328.

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 82391 - 2² = 82387 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82393) 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, 830 + ... + 923.

It is an arithmetic number, because the mean of its divisors is an integer number (21048).

2⁸²³⁹¹ is an apocalyptic number.

82391 is a deficient number, since it is larger than the sum of its proper divisors (1801).

82391 is a wasteful number, since it uses less digits than its factorization.

82391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1800.

The product of its digits is 432, while the sum is 23.

The square root of 82391 is about 287.0383249672. The cubic root of 82391 is about 43.5137579242.

The spelling of 82391 in words is "eighty-two thousand, three hundred ninety-one".