20002200021 has 10 divisors (see below), whose sum is σ = 29879829782. Its totient is φ = 13334799960.

The previous prime is 20002200019. The next prime is 20002200047. The reversal of 20002200021 is 12000220002.

It can be written as a sum of positive squares in only one way, i.e., 15305153796 + 4697046225 = 123714^2 + 68535^2 .

It is not a de Polignac number, because 20002200021 - 2¹ = 20002200019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20002199976 and 20002200012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20002202021) 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 9 ways as a sum of consecutive naturals, for example, 123470290 + ... + 123470451.

Almost surely, 2^20002200021 is an apocalyptic number.

It is an amenable number.

20002200021 is a deficient number, since it is larger than the sum of its proper divisors (9877629761).

20002200021 is an equidigital number, since it uses as much as digits as its factorization.

20002200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246940753 (or 246940744 counting only the distinct ones).

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

Adding to 20002200021 its reverse (12000220002), we get a palindrome (32002420023).

The spelling of 20002200021 in words is "twenty billion, two million, two hundred thousand, twenty-one".