20104209 has 12 divisors (see below), whose sum is σ = 29824756. Its totient is φ = 13040352.

The previous prime is 20104207. The next prime is 20104229. The reversal of 20104209 is 90240102.

It can be written as a sum of positive squares in 2 ways, for example, as 15681600 + 4422609 = 3960^2 + 2103^2 .

It is not a de Polignac number, because 20104209 - 2¹ = 20104207 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20104191 and 20104200.

It is not an unprimeable number, because it can be changed into a prime (20104207) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29854 + ... + 30519.

Almost surely, 2^20104209 is an apocalyptic number.

It is an amenable number.

20104209 is a deficient number, since it is larger than the sum of its proper divisors (9720547).

20104209 is a wasteful number, since it uses less digits than its factorization.

20104209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60416 (or 60413 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 20104209 is about 4483.7717381687. The cubic root of 20104209 is about 271.9123897844.

The spelling of 20104209 in words is "twenty million, one hundred four thousand, two hundred nine".