210000200021 has 4 divisors (see below), whose sum is σ = 210007372044. Its totient is φ = 209993028000.

The previous prime is 210000200009. The next prime is 210000200027. The reversal of 210000200021 is 120002000012.

210000200021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 47474308996 + 162525891025 = 217886^2 + 403145^2 .

It is a cyclic number.

It is not a de Polignac number, because 210000200021 - 2²² = 209996005717 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210000199981 and 210000200008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210000200027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3541910 + ... + 3600711.

It is an arithmetic number, because the mean of its divisors is an integer number (52501843011).

Almost surely, 2^210000200021 is an apocalyptic number.

It is an amenable number.

210000200021 is a deficient number, since it is larger than the sum of its proper divisors (7172023).

210000200021 is an equidigital number, since it uses as much as digits as its factorization.

210000200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7172022.

The product of its (nonzero) digits is 8, while the sum is 8.

Adding to 210000200021 its reverse (120002000012), we get a palindrome (330002200033).

Subtracting from 210000200021 its reverse (120002000012), we obtain a square (89998200009 = 299997²).

The spelling of 210000200021 in words is "two hundred ten billion, two hundred thousand, twenty-one".