21112210221 has 16 divisors (see below), whose sum is σ = 30652939200. Its totient is φ = 12874232448.

The previous prime is 21112210199. The next prime is 21112210243. The reversal of 21112210221 is 12201221112.

It is an interprime number because it is at equal distance from previous prime (21112210199) and next prime (21112210243).

It is not a de Polignac number, because 21112210221 - 2⁶ = 21112210157 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21112210221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112210321) 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 15 ways as a sum of consecutive naturals, for example, 6384376 + ... + 6387681.

It is an arithmetic number, because the mean of its divisors is an integer number (1915808700).

Almost surely, 2^21112210221 is an apocalyptic number.

It is an amenable number.

21112210221 is a deficient number, since it is larger than the sum of its proper divisors (9540728979).

21112210221 is a wasteful number, since it uses less digits than its factorization.

21112210221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12772108.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21112210221 its reverse (12201221112), we get a palindrome (33313431333).

The spelling of 21112210221 in words is "twenty-one billion, one hundred twelve million, two hundred ten thousand, two hundred twenty-one".