20204004421 has 4 divisors (see below), whose sum is σ = 20206735852. Its totient is φ = 20201272992.

The previous prime is 20204004413. The next prime is 20204004487. The reversal of 20204004421 is 12440040202.

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 16135350625 + 4068653796 = 127025^2 + 63786^2 .

It is a cyclic number.

It is not a de Polignac number, because 20204004421 - 2³ = 20204004413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20204004221) 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, 1354590 + ... + 1369423.

It is an arithmetic number, because the mean of its divisors is an integer number (5051683963).

Almost surely, 2^20204004421 is an apocalyptic number.

It is an amenable number.

20204004421 is a deficient number, since it is larger than the sum of its proper divisors (2731431).

20204004421 is an equidigital number, since it uses as much as digits as its factorization.

20204004421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2731430.

The product of its (nonzero) digits is 512, while the sum is 19.

Adding to 20204004421 its reverse (12440040202), we get a palindrome (32644044623).

The spelling of 20204004421 in words is "twenty billion, two hundred four million, four thousand, four hundred twenty-one".