21200220001 has 4 divisors (see below), whose sum is σ = 21931262100. Its totient is φ = 20469177904.

The previous prime is 21200219987. The next prime is 21200220049. The reversal of 21200220001 is 10002200212.

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 3803928976 + 17396291025 = 61676^2 + 131895^2 .

It is a cyclic number.

It is not a de Polignac number, because 21200220001 - 2²⁹ = 20663349089 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21200220001.

It is not an unprimeable number, because it can be changed into a prime (21200220101) 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, 365521006 + ... + 365521063.

It is an arithmetic number, because the mean of its divisors is an integer number (5482815525).

Almost surely, 2^21200220001 is an apocalyptic number.

It is an amenable number.

21200220001 is a deficient number, since it is larger than the sum of its proper divisors (731042099).

21200220001 is an equidigital number, since it uses as much as digits as its factorization.

21200220001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 731042098.

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 21200220001 its reverse (10002200212), we get a palindrome (31202420213).

The spelling of 21200220001 in words is "twenty-one billion, two hundred million, two hundred twenty thousand, one".