82191 has 4 divisors (see below), whose sum is σ = 109592. Its totient is φ = 54792.

The previous prime is 82189. The next prime is 82193. The reversal of 82191 is 19128.

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

It is an interprime number because it is at equal distance from previous prime (82189) and next prime (82193).

It is not a de Polignac number, because 82191 - 2¹ = 82189 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13696 + ... + 13701.

It is an arithmetic number, because the mean of its divisors is an integer number (27398).

2⁸²¹⁹¹ is an apocalyptic number.

82191 is a deficient number, since it is larger than the sum of its proper divisors (27401).

82191 is a wasteful number, since it uses less digits than its factorization.

82191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27400.

The product of its digits is 144, while the sum is 21.

The square root of 82191 is about 286.6897277546. The cubic root of 82191 is about 43.4785202448.

The spelling of 82191 in words is "eighty-two thousand, one hundred ninety-one".