210221221021 has 8 divisors (see below), whose sum is σ = 240255745664. Its totient is φ = 180187426800.

The previous prime is 210221220997. The next prime is 210221221027. The reversal of 210221221021 is 120122122012.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 210221221021 - 2⁹ = 210221220509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210221220986 and 210221221004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210221221027) 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 7 ways as a sum of consecutive naturals, for example, 755296 + ... + 995446.

It is an arithmetic number, because the mean of its divisors is an integer number (30031968208).

Almost surely, 2^210221221021 is an apocalyptic number.

It is an amenable number.

210221221021 is a deficient number, since it is larger than the sum of its proper divisors (30034524643).

210221221021 is a wasteful number, since it uses less digits than its factorization.

210221221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365211.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 210221221021 its reverse (120122122012), we get a palindrome (330343343033).

Subtracting from 210221221021 its reverse (120122122012), we obtain a palindrome (90099099009).

The spelling of 210221221021 in words is "two hundred ten billion, two hundred twenty-one million, two hundred twenty-one thousand, twenty-one".