21589013 has 2 divisors, whose sum is σ = 21589014. Its totient is φ = 21589012.

The previous prime is 21589003. The next prime is 21589037. The reversal of 21589013 is 31098512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15547249 + 6041764 = 3943^2 + 2458^2 .

It is a cyclic number.

It is not a de Polignac number, because 21589013 - 2²⁴ = 4811797 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is equal to p_1364852 and since 21589013 and 1364852 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21589003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10794506 + 10794507.

It is an arithmetic number, because the mean of its divisors is an integer number (10794507).

Almost surely, 2^21589013 is an apocalyptic number.

It is an amenable number.

21589013 is a deficient number, since it is larger than the sum of its proper divisors (1).

21589013 is an equidigital number, since it uses as much as digits as its factorization.

21589013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 21589013 is about 4646.3978521001. The cubic root of 21589013 is about 278.4481024375.

The spelling of 21589013 in words is "twenty-one million, five hundred eighty-nine thousand, thirteen".