21311114121216 has 364 divisors, whose sum is σ = 64073707215232. Its totient is φ = 7083984273408.

The previous prime is 21311114121203. The next prime is 21311114121221. The reversal of 21311114121216 is 61212141111312.

21311114121216 is a `hidden beast` number, since 2 + 1 + 31 + 1 + 1 + 1 + 412 + 1 + 216 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is an insolite number, because it is divisible by the sum (81) and by the product (331776) of the squares of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 21311114121216.

It is an unprimeable number.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 1095846405 + ... + 1095865851.

Almost surely, 2^{21311114121216} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21311114121216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32036853607616).

21311114121216 is an abundant number, since it is smaller than the sum of its proper divisors (42762593094016).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21311114121216 is an frugal number, since it uses more digits than its factorization.

21311114121216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19856 (or 19819 counting only the distinct ones).

The product of its digits is 576, while the sum is 27.

Adding to 21311114121216 its reverse (61212141111312), we get a palindrome (82523255232528).

The spelling of 21311114121216 in words is "twenty-one trillion, three hundred eleven billion, one hundred fourteen million, one hundred twenty-one thousand, two hundred sixteen".