21201112011011 has 4 divisors (see below), whose sum is σ = 21328064777712. Its totient is φ = 21074159244312.

The previous prime is 21201112010989. The next prime is 21201112011067. The reversal of 21201112011011 is 11011021110212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21201112011011 - 2¹⁸ = 21201111748867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21201112011071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63476383100 + ... + 63476383433.

It is an arithmetic number, because the mean of its divisors is an integer number (5332016194428).

Almost surely, 2^{21201112011011} is an apocalyptic number.

21201112011011 is a deficient number, since it is larger than the sum of its proper divisors (126952766701).

21201112011011 is a wasteful number, since it uses less digits than its factorization.

21201112011011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126952766700.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21201112011011 its reverse (11011021110212), we get a palindrome (32212133121223).

The spelling of 21201112011011 in words is "twenty-one trillion, two hundred one billion, one hundred twelve million, eleven thousand, eleven".