81923 has 8 divisors (see below), whose sum is σ = 89280. Its totient is φ = 74880.

The previous prime is 81919. The next prime is 81929. The reversal of 81923 is 32918.

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 81923 - 2² = 81919 is a prime.

It is a super-2 number, since 2×81923² = 13422755858, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81929) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 998 + ... + 1076.

It is an arithmetic number, because the mean of its divisors is an integer number (11160).

2⁸¹⁹²³ is an apocalyptic number.

81923 is a deficient number, since it is larger than the sum of its proper divisors (7357).

81923 is a wasteful number, since it uses less digits than its factorization.

81923 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157.

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

The square root of 81923 is about 286.2219418563. The cubic root of 81923 is about 43.4312120187.

The spelling of 81923 in words is "eighty-one thousand, nine hundred twenty-three".