23181 has 4 divisors (see below), whose sum is σ = 30912. Its totient is φ = 15452.

The previous prime is 23173. The next prime is 23189. The reversal of 23181 is 18132.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (23173) and next prime (23189).

It is a cyclic number.

It is not a de Polignac number, because 23181 - 2³ = 23173 is a prime.

It is a super-2 number, since 2×23181² = 1074717522, which contains 22 as substring.

It is a D-number.

It is a nialpdrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 23181.

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 23181.

It is not an unprimeable number, because it can be changed into a prime (23189) 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, 3861 + ... + 3866.

It is an arithmetic number, because the mean of its divisors is an integer number (7728).

2²³¹⁸¹ is an apocalyptic number.

It is an amenable number.

23181 is a deficient number, since it is larger than the sum of its proper divisors (7731).

23181 is an equidigital number, since it uses as much as digits as its factorization.

23181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7730.

The product of its digits is 48, while the sum is 15.

The square root of 23181 is about 152.2530787866. The cubic root of 23181 is about 28.5130749487.

The spelling of 23181 in words is "twenty-three thousand, one hundred eighty-one".