210021000221 has 4 divisors (see below), whose sum is σ = 210022096032. Its totient is φ = 210019904412.

The previous prime is 210021000199. The next prime is 210021000239. The reversal of 210021000221 is 122000120012.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 210021000221 - 2⁶ = 210021000157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210021000281) 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 3 ways as a sum of consecutive naturals, for example, 176495 + ... + 671708.

It is an arithmetic number, because the mean of its divisors is an integer number (52505524008).

Almost surely, 2^210021000221 is an apocalyptic number.

It is an amenable number.

210021000221 is a deficient number, since it is larger than the sum of its proper divisors (1095811).

210021000221 is an equidigital number, since it uses as much as digits as its factorization.

210021000221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1095810.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 210021000221 its reverse (122000120012), we get a palindrome (332021120233).

The spelling of 210021000221 in words is "two hundred ten billion, twenty-one million, two hundred twenty-one", and thus it is an aban number.