22042021021 has 4 divisors (see below), whose sum is σ = 22043036412. Its totient is φ = 22041005632.

The previous prime is 22042021019. The next prime is 22042021069. The reversal of 22042021021 is 12012024022.

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 19758519225 + 2283501796 = 140565^2 + 47786^2 .

It is a cyclic number.

It is not a de Polignac number, because 22042021021 - 2¹ = 22042021019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22042020986 and 22042021004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22042021081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 474406 + ... + 518791.

It is an arithmetic number, because the mean of its divisors is an integer number (5510759103).

Almost surely, 2^22042021021 is an apocalyptic number.

It is an amenable number.

22042021021 is a deficient number, since it is larger than the sum of its proper divisors (1015391).

22042021021 is an equidigital number, since it uses as much as digits as its factorization.

22042021021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1015390.

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 22042021021 its reverse (12012024022), we get a palindrome (34054045043).

The spelling of 22042021021 in words is "twenty-two billion, forty-two million, twenty-one thousand, twenty-one".