21839504 has 10 divisors (see below), whose sum is σ = 42314070. Its totient is φ = 10919744.

The previous prime is 21839497. The next prime is 21839507. The reversal of 21839504 is 40593812.

It can be written as a sum of positive squares in only one way, i.e., 21715600 + 123904 = 4660^2 + 352^2 .

It is not an unprimeable number, because it can be changed into a prime (21839507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 682469 + ... + 682500.

It is an arithmetic number, because the mean of its divisors is an integer number (4231407).

Almost surely, 2^21839504 is an apocalyptic number.

It is an amenable number.

21839504 is a deficient number, since it is larger than the sum of its proper divisors (20474566).

21839504 is a wasteful number, since it uses less digits than its factorization.

21839504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1364977 (or 1364971 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 21839504 is about 4673.2755108168. The cubic root of 21839504 is about 279.5208813096.

The spelling of 21839504 in words is "twenty-one million, eight hundred thirty-nine thousand, five hundred four".