20604 has 24 divisors (see below), whose sum is σ = 51408. Its totient is φ = 6400.

The previous prime is 20599. The next prime is 20611. The reversal of 20604 is 40602.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a nialpdrome in base 12.

It is a self number, because there is not a number n which added to its sum of digits gives 20604.

It is a congruent number.

It is an unprimeable number.

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, 154 + ... + 254.

It is an arithmetic number, because the mean of its divisors is an integer number (2142).

2²⁰⁶⁰⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20604, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25704).

20604 is an abundant number, since it is smaller than the sum of its proper divisors (30804).

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

20604 is a wasteful number, since it uses less digits than its factorization.

20604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125 (or 123 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 12.

The square root of 20604 is about 143.5409349280. The cubic root of 20604 is about 27.4147220509.

The spelling of 20604 in words is "twenty thousand, six hundred four".