20533009 has 8 divisors (see below), whose sum is σ = 23945600. Its totient is φ = 17599428.

The previous prime is 20533001. The next prime is 20533049. The reversal of 20533009 is 90033502.

It is not a de Polignac number, because 20533009 - 2³ = 20533001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20533001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29589 + ... + 30274.

It is an arithmetic number, because the mean of its divisors is an integer number (2993200).

Almost surely, 2^20533009 is an apocalyptic number.

It is an amenable number.

20533009 is a deficient number, since it is larger than the sum of its proper divisors (3412591).

20533009 is an frugal number, since it uses more digits than its factorization.

20533009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59884 (or 59870 counting only the distinct ones).

The product of its (nonzero) digits is 810, while the sum is 22.

The square root of 20533009 is about 4531.3363371085. The cubic root of 20533009 is about 273.8320004828.

The spelling of 20533009 in words is "twenty million, five hundred thirty-three thousand, nine".