20388 has 12 divisors (see below), whose sum is σ = 47600. Its totient is φ = 6792.

The previous prime is 20369. The next prime is 20389. The reversal of 20388 is 88302.

20388 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (20389) by changing a digit.

20388 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 838 + ... + 861.

2²⁰³⁸⁸ is an apocalyptic number.

It is an amenable number.

20388 is an abundant number, since it is smaller than the sum of its proper divisors (27212).

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 (23800).

20388 is a wasteful number, since it uses less digits than its factorization.

20388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1706 (or 1704 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 20388 is about 142.7865539888. The cubic root of 20388 is about 27.3185854740.

The spelling of 20388 in words is "twenty thousand, three hundred eighty-eight".