21210112011221 has 8 divisors (see below), whose sum is σ = 24650977640640. Its totient is φ = 17871958788768.

The previous prime is 21210112011169. The next prime is 21210112011227. The reversal of 21210112011221 is 12211021101212.

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

It is a de Polignac number, because none of the positive numbers 2^k-21210112011221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21210112011221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210112011227) 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 7 ways as a sum of consecutive naturals, for example, 25678101296 + ... + 25678102121.

It is an arithmetic number, because the mean of its divisors is an integer number (3081372205080).

Almost surely, 2^{21210112011221} is an apocalyptic number.

It is an amenable number.

21210112011221 is a deficient number, since it is larger than the sum of its proper divisors (3440865629419).

21210112011221 is an equidigital number, since it uses as much as digits as its factorization.

21210112011221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51356203483.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21210112011221 its reverse (12211021101212), we get a palindrome (33421133112433).

The spelling of 21210112011221 in words is "twenty-one trillion, two hundred ten billion, one hundred twelve million, eleven thousand, two hundred twenty-one".