21438352 has 20 divisors (see below), whose sum is σ = 44732380. Its totient is φ = 9894528.

The previous prime is 21438349. The next prime is 21438353. The reversal of 21438352 is 25383412.

It can be written as a sum of positive squares in 2 ways, for example, as 10784656 + 10653696 = 3284^2 + 3264^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21438352.

It is not an unprimeable number, because it can be changed into a prime (21438353) 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, 51327 + ... + 51742.

It is an arithmetic number, because the mean of its divisors is an integer number (2236619).

Almost surely, 2^21438352 is an apocalyptic number.

It is an amenable number.

21438352 is an abundant number, since it is smaller than the sum of its proper divisors (23294028).

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

21438352 is a wasteful number, since it uses less digits than its factorization.

21438352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103090 (or 103084 counting only the distinct ones).

The product of its digits is 5760, while the sum is 28.

The square root of 21438352 is about 4630.1568008006. The cubic root of 21438352 is about 277.7988642244.

The spelling of 21438352 in words is "twenty-one million, four hundred thirty-eight thousand, three hundred fifty-two".