20385 has 16 divisors (see below), whose sum is σ = 36480. Its totient is φ = 10800.

The previous prime is 20369. The next prime is 20389. The reversal of 20385 is 58302.

20385 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 20385 - 2⁴ = 20369 is a prime.

It is a Curzon number.

20385 is a lucky number.

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

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 60 + ... + 210.

It is an arithmetic number, because the mean of its divisors is an integer number (2280).

2²⁰³⁸⁵ is an apocalyptic number.

It is an amenable number.

20385 is a deficient number, since it is larger than the sum of its proper divisors (16095).

20385 is a wasteful number, since it uses less digits than its factorization.

20385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 20385 is about 142.7760484115. The cubic root of 20385 is about 27.3172454737.

Adding to 20385 its reverse (58302), we get a palindrome (78687).

The spelling of 20385 in words is "twenty thousand, three hundred eighty-five".