20204261809 has 4 divisors (see below), whose sum is σ = 20317134960. Its totient is φ = 20091388660.

The previous prime is 20204261783. The next prime is 20204261821. The reversal of 20204261809 is 90816240202.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20204261809 - 2¹³ = 20204253617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20234261809) 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, 56436307 + ... + 56436664.

It is an arithmetic number, because the mean of its divisors is an integer number (5079283740).

Almost surely, 2^20204261809 is an apocalyptic number.

It is an amenable number.

20204261809 is a deficient number, since it is larger than the sum of its proper divisors (112873151).

20204261809 is a wasteful number, since it uses less digits than its factorization.

20204261809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112873150.

The product of its (nonzero) digits is 13824, while the sum is 34.

The spelling of 20204261809 in words is "twenty billion, two hundred four million, two hundred sixty-one thousand, eight hundred nine".