21231124110221 has 4 divisors (see below), whose sum is σ = 21232542464700. Its totient is φ = 21229705755744.

The previous prime is 21231124110169. The next prime is 21231124110359. The reversal of 21231124110221 is 12201142113212.

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 3297169587721 + 17933954522500 = 1815811^2 + 4234850^2 .

It is a cyclic number.

It is not a de Polignac number, because 21231124110221 - 2³⁴ = 21213944241037 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 (21231124110821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 709154786 + ... + 709184723.

It is an arithmetic number, because the mean of its divisors is an integer number (5308135616175).

Almost surely, 2^{21231124110221} is an apocalyptic number.

It is an amenable number.

21231124110221 is a deficient number, since it is larger than the sum of its proper divisors (1418354479).

21231124110221 is a wasteful number, since it uses less digits than its factorization.

21231124110221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1418354478.

The product of its (nonzero) digits is 384, while the sum is 23.

Adding to 21231124110221 its reverse (12201142113212), we get a palindrome (33432266223433).

The spelling of 21231124110221 in words is "twenty-one trillion, two hundred thirty-one billion, one hundred twenty-four million, one hundred ten thousand, two hundred twenty-one".