20433209 has 4 divisors (see below), whose sum is σ = 20635620. Its totient is φ = 20230800.

The previous prime is 20433181. The next prime is 20433229. The reversal of 20433209 is 90233402.

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 19536400 + 896809 = 4420^2 + 947^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20433209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20433229) 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, 101054 + ... + 101255.

It is an arithmetic number, because the mean of its divisors is an integer number (5158905).

Almost surely, 2^20433209 is an apocalyptic number.

It is an amenable number.

20433209 is a deficient number, since it is larger than the sum of its proper divisors (202411).

20433209 is a wasteful number, since it uses less digits than its factorization.

20433209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202410.

The product of its (nonzero) digits is 1296, while the sum is 23.

The square root of 20433209 is about 4520.3107194086. The cubic root of 20433209 is about 273.3876293419.

The spelling of 20433209 in words is "twenty million, four hundred thirty-three thousand, two hundred nine".