22020000021 has 6 divisors (see below), whose sum is σ = 31806666710. Its totient is φ = 14680000008.

The previous prime is 22020000017. The next prime is 22020000043. The reversal of 22020000021 is 12000002022.

It can be written as a sum of positive squares in only one way, i.e., 20774898225 + 1245101796 = 144135^2 + 35286^2 .

It is not a de Polignac number, because 22020000021 - 2² = 22020000017 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 2446666669 = 22020000021 / (2 + 2 + 0 + 2 + 0 + 0 + 0 + 0 + 0 + 2 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22019999958 and 22020000012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22020000721) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1223333326 + ... + 1223333343.

Almost surely, 2^22020000021 is an apocalyptic number.

It is an amenable number.

22020000021 is a deficient number, since it is larger than the sum of its proper divisors (9786666689).

22020000021 is a wasteful number, since it uses less digits than its factorization.

22020000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2446666675 (or 2446666672 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

Adding to 22020000021 its reverse (12000002022), we get a palindrome (34020002043).

The spelling of 22020000021 in words is "twenty-two billion, twenty million, twenty-one", and thus it is an aban number and an uban number.