20039904 has 72 divisors (see below), whose sum is σ = 57493800. Its totient is φ = 6620928.

The previous prime is 20039893. The next prime is 20039933. The reversal of 20039904 is 40993002.

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 42679 + ... + 43145.

It is an arithmetic number, because the mean of its divisors is an integer number (798525).

Almost surely, 2^20039904 is an apocalyptic number.

20039904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20039904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28746900).

20039904 is an abundant number, since it is smaller than the sum of its proper divisors (37453896).

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

20039904 is a wasteful number, since it uses less digits than its factorization.

20039904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 632 (or 621 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 20039904 is about 4476.5951346978. The cubic root of 20039904 is about 271.6221685976.

It can be divided in two parts, 200 and 39904, that added together give a palindrome (40104).

The spelling of 20039904 in words is "twenty million, thirty-nine thousand, nine hundred four".