20430209 has 8 divisors (see below), whose sum is σ = 22330368. Its totient is φ = 18607680.

The previous prime is 20430191. The next prime is 20430251. The reversal of 20430209 is 90203402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20430209 - 2²⁰ = 19381633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20430409) 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, 18857 + ... + 19910.

It is an arithmetic number, because the mean of its divisors is an integer number (2791296).

Almost surely, 2^20430209 is an apocalyptic number.

It is an amenable number.

20430209 is a deficient number, since it is larger than the sum of its proper divisors (1900159).

20430209 is a wasteful number, since it uses less digits than its factorization.

20430209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38815.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 20430209 is about 4519.9788716320. The cubic root of 20430209 is about 273.3742491132.

The spelling of 20430209 in words is "twenty million, four hundred thirty thousand, two hundred nine".