21011122101111 has 8 divisors (see below), whose sum is σ = 28014914763264. Its totient is φ = 14007372086520.

The previous prime is 21011122101107. The next prime is 21011122101143. The reversal of 21011122101111 is 11110122111012.

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

It is not a de Polignac number, because 21011122101111 - 2² = 21011122101107 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011122141111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9494055 + ... + 11496056.

It is an arithmetic number, because the mean of its divisors is an integer number (3501864345408).

Almost surely, 2^{21011122101111} is an apocalyptic number.

21011122101111 is a deficient number, since it is larger than the sum of its proper divisors (7003792662153).

21011122101111 is a wasteful number, since it uses less digits than its factorization.

21011122101111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21323781.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 21011122101111 its reverse (11110122111012), we get a palindrome (32121244212123).

Subtracting from 21011122101111 its reverse (11110122111012), we obtain a palindrome (9900999990099).

The spelling of 21011122101111 in words is "twenty-one trillion, eleven billion, one hundred twenty-two million, one hundred one thousand, one hundred eleven".