21443028 has 24 divisors (see below), whose sum is σ = 50148000. Its totient is φ = 7131360.

The previous prime is 21443003. The next prime is 21443033. The reversal of 21443028 is 82034412.

It is a junction number, because it is equal to n+sod(n) for n = 21442989 and 21443007.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4198 + ... + 7778.

It is an arithmetic number, because the mean of its divisors is an integer number (2089500).

Almost surely, 2^21443028 is an apocalyptic number.

It is an amenable number.

21443028 is an abundant number, since it is smaller than the sum of its proper divisors (28704972).

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

21443028 is a wasteful number, since it uses less digits than its factorization.

21443028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4087 (or 4085 counting only the distinct ones).

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

The square root of 21443028 is about 4630.6617237712. The cubic root of 21443028 is about 277.8190600097.

The spelling of 21443028 in words is "twenty-one million, four hundred forty-three thousand, twenty-eight".