21893728 has 24 divisors (see below), whose sum is σ = 44023392. Its totient is φ = 10713216.

The previous prime is 21893699. The next prime is 21893747. The reversal of 21893728 is 82739812.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5775 + ... + 8782.

It is an arithmetic number, because the mean of its divisors is an integer number (1834308).

Almost surely, 2^21893728 is an apocalyptic number.

It is an amenable number.

21893728 is an abundant number, since it is smaller than the sum of its proper divisors (22129664).

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

21893728 is a wasteful number, since it uses less digits than its factorization.

21893728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14614 (or 14606 counting only the distinct ones).

The product of its digits is 48384, while the sum is 40.

The square root of 21893728 is about 4679.0734125465. The cubic root of 21893728 is about 279.7520253506.

The spelling of 21893728 in words is "twenty-one million, eight hundred ninety-three thousand, seven hundred twenty-eight".