20324209 has 4 divisors (see below), whose sum is σ = 20339316. Its totient is φ = 20309104.

The previous prime is 20324207. The next prime is 20324221. The reversal of 20324209 is 90242302.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6656400 + 13667809 = 2580^2 + 3697^2 .

It is a cyclic number.

It is not a de Polignac number, because 20324209 - 2¹ = 20324207 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20324209.

It is not an unprimeable number, because it can be changed into a prime (20324201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5314 + ... + 8299.

It is an arithmetic number, because the mean of its divisors is an integer number (5084829).

Almost surely, 2^20324209 is an apocalyptic number.

It is an amenable number.

20324209 is a deficient number, since it is larger than the sum of its proper divisors (15107).

20324209 is a wasteful number, since it uses less digits than its factorization.

20324209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15106.

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 20324209 is about 4508.2379041040. The cubic root of 20324209 is about 272.9006378507.

It can be divided in two parts, 2032 and 4209, that added together give a square (6241 = 79²).

The spelling of 20324209 in words is "twenty million, three hundred twenty-four thousand, two hundred nine".