21100111011111 has 8 divisors (see below), whose sum is σ = 30691070561664. Its totient is φ = 12787946067320.

The previous prime is 21100111011071. The next prime is 21100111011131. The reversal of 21100111011111 is 11111011100112.

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

It is a cyclic number.

It is not a de Polignac number, because 21100111011111 - 2³³ = 21091521076519 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100111011131) 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, 319698651651 + ... + 319698651716.

It is an arithmetic number, because the mean of its divisors is an integer number (3836383820208).

Almost surely, 2^{21100111011111} is an apocalyptic number.

21100111011111 is a deficient number, since it is larger than the sum of its proper divisors (9590959550553).

21100111011111 is a wasteful number, since it uses less digits than its factorization.

21100111011111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 639397303381.

The product of its (nonzero) digits is 2, while the sum is 12.

Adding to 21100111011111 its reverse (11111011100112), we get a palindrome (32211122111223).

The spelling of 21100111011111 in words is "twenty-one trillion, one hundred billion, one hundred eleven million, eleven thousand, one hundred eleven".