20259904 has 56 divisors (see below), whose sum is σ = 47109888. Its totient is φ = 8463360.

The previous prime is 20259887. The next prime is 20259913. The reversal of 20259904 is 40995202.

It is a tau number, because it is divible by the number of its divisors (56).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17817 + ... + 18919.

It is an arithmetic number, because the mean of its divisors is an integer number (841248).

Almost surely, 2^20259904 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 20259904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23554944).

20259904 is an abundant number, since it is smaller than the sum of its proper divisors (26849984).

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

20259904 is a wasteful number, since it uses less digits than its factorization.

20259904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1163 (or 1153 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 20259904 is about 4501.1003099242. The cubic root of 20259904 is about 272.6125181326.

It can be divided in two parts, 202 and 59904, that added together give a palindrome (60106).

The spelling of 20259904 in words is "twenty million, two hundred fifty-nine thousand, nine hundred four".