21137589 has 24 divisors (see below), whose sum is σ = 33696000. Its totient is φ = 12661440.

The previous prime is 21137563. The next prime is 21137609. The reversal of 21137589 is 98573112.

It is not a de Polignac number, because 21137589 - 2⁷ = 21137461 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21137539) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7612 + ... + 10010.

It is an arithmetic number, because the mean of its divisors is an integer number (1404000).

Almost surely, 2^21137589 is an apocalyptic number.

It is an amenable number.

21137589 is a deficient number, since it is larger than the sum of its proper divisors (12558411).

21137589 is a wasteful number, since it uses less digits than its factorization.

21137589 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2505 (or 2502 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 21137589 is about 4597.5633763984. The cubic root of 21137589 is about 276.4936423998.

The spelling of 21137589 in words is "twenty-one million, one hundred thirty-seven thousand, five hundred eighty-nine".