20589581 has 4 divisors (see below), whose sum is σ = 20680512. Its totient is φ = 20498652.

The previous prime is 20589571. The next prime is 20589589. The reversal of 20589581 is 18598502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20589581 is a prime.

It is a super-2 number, since 2×20589581² = 847861691511122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20589589) 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 in 3 ways as a sum of consecutive naturals, for example, 45125 + ... + 45578.

It is an arithmetic number, because the mean of its divisors is an integer number (5170128).

Almost surely, 2^20589581 is an apocalyptic number.

It is an amenable number.

20589581 is a deficient number, since it is larger than the sum of its proper divisors (90931).

20589581 is an equidigital number, since it uses as much as digits as its factorization.

20589581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90930.

The product of its (nonzero) digits is 28800, while the sum is 38.

The square root of 20589581 is about 4537.5743520079. The cubic root of 20589581 is about 274.0832547545.

The spelling of 20589581 in words is "twenty million, five hundred eighty-nine thousand, five hundred eighty-one".