23820 has 24 divisors (see below), whose sum is σ = 66864. Its totient is φ = 6336.

The previous prime is 23819. The next prime is 23827. The reversal of 23820 is 2832.

23820 = 2² + 3² + ... + 41².

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 23820.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 23820.

It is not an unprimeable number, because it can be changed into a prime (23827) 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 7 ways as a sum of consecutive naturals, for example, 139 + ... + 258.

It is an arithmetic number, because the mean of its divisors is an integer number (2786).

2²³⁸²⁰ is an apocalyptic number.

23820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23820 is an abundant number, since it is smaller than the sum of its proper divisors (43044).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33432).

23820 is a wasteful number, since it uses less digits than its factorization.

23820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 409 (or 407 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 23820 is about 154.3372929658. The cubic root of 23820 is about 28.7726978915.

The spelling of 23820 in words is "twenty-three thousand, eight hundred twenty".