21321110121 has 8 divisors (see below), whose sum is σ = 28430385120. Its totient is φ = 14212954272.

The previous prime is 21321110081. The next prime is 21321110149. The reversal of 21321110121 is 12101112312.

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

It is not a de Polignac number, because 21321110121 - 2⁹ = 21321109609 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21321110121.

It is not an unprimeable number, because it can be changed into a prime (21321110821) 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 7 ways as a sum of consecutive naturals, for example, 234276 + ... + 312293.

It is an arithmetic number, because the mean of its divisors is an integer number (3553798140).

Almost surely, 2^21321110121 is an apocalyptic number.

It is an amenable number.

21321110121 is a deficient number, since it is larger than the sum of its proper divisors (7109274999).

21321110121 is a wasteful number, since it uses less digits than its factorization.

21321110121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 559575.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 21321110121 its reverse (12101112312), we get a palindrome (33422222433).

The spelling of 21321110121 in words is "twenty-one billion, three hundred twenty-one million, one hundred ten thousand, one hundred twenty-one".