210221033021 has 4 divisors (see below), whose sum is σ = 210222224700. Its totient is φ = 210219841344.

The previous prime is 210221032997. The next prime is 210221033047. The reversal of 210221033021 is 120330122012.

210221033021 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, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 155799141796 + 54421891225 = 394714^2 + 233285^2 .

It is a cyclic number.

It is not a de Polignac number, because 210221033021 - 2¹⁰ = 210221031997 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210221023021) 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, 272876 + ... + 703493.

It is an arithmetic number, because the mean of its divisors is an integer number (52555556175).

Almost surely, 2^210221033021 is an apocalyptic number.

It is an amenable number.

210221033021 is a deficient number, since it is larger than the sum of its proper divisors (1191679).

210221033021 is an equidigital number, since it uses as much as digits as its factorization.

210221033021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1191678.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 210221033021 its reverse (120330122012), we get a palindrome (330551155033).

The spelling of 210221033021 in words is "two hundred ten billion, two hundred twenty-one million, thirty-three thousand, twenty-one".