20042440221 has 4 divisors (see below), whose sum is σ = 26723253632. Its totient is φ = 13361626812.

The previous prime is 20042440219. The next prime is 20042440283. The reversal of 20042440221 is 12204424002.

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 not a de Polignac number, because 20042440221 - 2¹ = 20042440219 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 (20042440721) 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, 3340406701 + ... + 3340406706.

It is an arithmetic number, because the mean of its divisors is an integer number (6680813408).

Almost surely, 2^20042440221 is an apocalyptic number.

It is an amenable number.

20042440221 is a deficient number, since it is larger than the sum of its proper divisors (6680813411).

20042440221 is an equidigital number, since it uses as much as digits as its factorization.

20042440221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6680813410.

The product of its (nonzero) digits is 1024, while the sum is 21.

Adding to 20042440221 its reverse (12204424002), we get a palindrome (32246864223).

The spelling of 20042440221 in words is "twenty billion, forty-two million, four hundred forty thousand, two hundred twenty-one".