22200020021 has 4 divisors (see below), whose sum is σ = 22200428652. Its totient is φ = 22199611392.

The previous prime is 22200020009. The next prime is 22200020039. The reversal of 22200020021 is 12002000222.

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 11790919396 + 10409100625 = 108586^2 + 102025^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22200020021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 22200019984 and 22200020011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22200020221) 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, 107546 + ... + 236571.

It is an arithmetic number, because the mean of its divisors is an integer number (5550107163).

Almost surely, 2^22200020021 is an apocalyptic number.

It is an amenable number.

22200020021 is a deficient number, since it is larger than the sum of its proper divisors (408631).

22200020021 is an equidigital number, since it uses as much as digits as its factorization.

22200020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408630.

The product of its (nonzero) digits is 32, while the sum is 11.

Adding to 22200020021 its reverse (12002000222), we get a palindrome (34202020243).

The spelling of 22200020021 in words is "twenty-two billion, two hundred million, twenty thousand, twenty-one".