21924538 has 8 divisors (see below), whose sum is σ = 32963040. Its totient is φ = 10936860.

The previous prime is 21924523. The next prime is 21924541. The reversal of 21924538 is 83542912.

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

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, 11608 + ... + 13363.

It is an arithmetic number, because the mean of its divisors is an integer number (4120380).

Almost surely, 2^21924538 is an apocalyptic number.

21924538 is a deficient number, since it is larger than the sum of its proper divisors (11038502).

21924538 is a wasteful number, since it uses less digits than its factorization.

21924538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25412.

The product of its digits is 17280, while the sum is 34.

The square root of 21924538 is about 4682.3645735889. The cubic root of 21924538 is about 279.8831910730.

The spelling of 21924538 in words is "twenty-one million, nine hundred twenty-four thousand, five hundred thirty-eight".