21030589 has 2 divisors, whose sum is σ = 21030590. Its totient is φ = 21030588.

The previous prime is 21030557. The next prime is 21030613. The reversal of 21030589 is 98503012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20160100 + 870489 = 4490^2 + 933^2 .

It is a cyclic number.

It is not a de Polignac number, because 21030589 - 2⁵ = 21030557 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is equal to p_1331785 and since 21030589 and 1331785 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 (21030389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515294 + 10515295.

It is an arithmetic number, because the mean of its divisors is an integer number (10515295).

Almost surely, 2^21030589 is an apocalyptic number.

It is an amenable number.

21030589 is a deficient number, since it is larger than the sum of its proper divisors (1).

21030589 is an equidigital number, since it uses as much as digits as its factorization.

21030589 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 28.

The square root of 21030589 is about 4585.9120139837. The cubic root of 21030589 is about 276.0263093663.

The spelling of 21030589 in words is "twenty-one million, thirty thousand, five hundred eighty-nine".