21043089 has 12 divisors (see below), whose sum is σ = 31995600. Its totient is φ = 13290264.

The previous prime is 21043069. The next prime is 21043097. The reversal of 21043089 is 98034012.

It is not a de Polignac number, because 21043089 - 2⁹ = 21042577 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21043019) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 61359 + ... + 61700.

It is an arithmetic number, because the mean of its divisors is an integer number (2666300).

Almost surely, 2^21043089 is an apocalyptic number.

It is an amenable number.

21043089 is a deficient number, since it is larger than the sum of its proper divisors (10952511).

21043089 is a wasteful number, since it uses less digits than its factorization.

21043089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123084 (or 123081 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 21043089 is about 4587.2746811151. The cubic root of 21043089 is about 276.0809860010.

The spelling of 21043089 in words is "twenty-one million, forty-three thousand, eighty-nine".