21024438 has 32 divisors (see below), whose sum is σ = 44499456. Its totient is φ = 6608448.

The previous prime is 21024433. The next prime is 21024457. The reversal of 21024438 is 83442012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21024433) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9031 + ... + 11117.

It is an arithmetic number, because the mean of its divisors is an integer number (1390608).

Almost surely, 2^21024438 is an apocalyptic number.

21024438 is an abundant number, since it is smaller than the sum of its proper divisors (23475018).

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

21024438 is a wasteful number, since it uses less digits than its factorization.

21024438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2188.

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 21024438 is about 4585.2413240744. The cubic root of 21024438 is about 275.9993961339. Note that the first 3 decimals are identical.

The spelling of 21024438 in words is "twenty-one million, twenty-four thousand, four hundred thirty-eight".