21438038 has 8 divisors (see below), whose sum is σ = 32223000. Its totient is φ = 10697040.

The previous prime is 21438029. The next prime is 21438041. The reversal of 21438038 is 83083412.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21438038.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9743 + ... + 11738.

It is an arithmetic number, because the mean of its divisors is an integer number (4027875).

Almost surely, 2^21438038 is an apocalyptic number.

21438038 is a deficient number, since it is larger than the sum of its proper divisors (10784962).

21438038 is a wasteful number, since it uses less digits than its factorization.

21438038 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21982.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 21438038 is about 4630.1228925375. The cubic root of 21438038 is about 277.7975079437.

The spelling of 21438038 in words is "twenty-one million, four hundred thirty-eight thousand, thirty-eight".