20589209 has 6 divisors (see below), whose sum is σ = 21523866. Its totient is φ = 19693520.

The previous prime is 20589203. The next prime is 20589211. The reversal of 20589209 is 90298502.

It can be written as a sum of positive squares in only one way, i.e., 10368400 + 10220809 = 3220^2 + 3197^2 .

It is not a de Polignac number, because 20589209 - 2¹⁶ = 20523673 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20589203) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 18932 + ... + 19989.

It is an arithmetic number, because the mean of its divisors is an integer number (3587311).

Almost surely, 2^20589209 is an apocalyptic number.

It is an amenable number.

20589209 is a deficient number, since it is larger than the sum of its proper divisors (934657).

20589209 is an equidigital number, since it uses as much as digits as its factorization.

20589209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38967 (or 38944 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 20589209 is about 4537.5333607589. The cubic root of 20589209 is about 274.0816040882.

The spelling of 20589209 in words is "twenty million, five hundred eighty-nine thousand, two hundred nine".