20804144 has 20 divisors (see below), whose sum is σ = 42061296. Its totient is φ = 9949632.

The previous prime is 20804137. The next prime is 20804149. The reversal of 20804144 is 44140802.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is not an unprimeable number, because it can be changed into a prime (20804149) 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, 27899 + ... + 28634.

Almost surely, 2^20804144 is an apocalyptic number.

It is an amenable number.

20804144 is an abundant number, since it is smaller than the sum of its proper divisors (21257152).

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

20804144 is a wasteful number, since it uses less digits than its factorization.

20804144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56564 (or 56558 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 23.

The square root of 20804144 is about 4561.1559938244. The cubic root of 20804144 is about 275.0320359373.

Adding to 20804144 its reverse (44140802), we get a palindrome (64944946).

The spelling of 20804144 in words is "twenty million, eight hundred four thousand, one hundred forty-four".