21111102111111 has 8 divisors (see below), whose sum is σ = 28264933394544. Its totient is φ = 14015669450880.

The previous prime is 21111102111109. The next prime is 21111102111131. The reversal of 21111102111111 is 11111120111112.

It is a happy number.

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

It is not a de Polignac number, because 21111102111111 - 2¹ = 21111102111109 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111102111131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14599654956 + ... + 14599656401.

It is an arithmetic number, because the mean of its divisors is an integer number (3533116674318).

Almost surely, 2^{21111102111111} is an apocalyptic number.

21111102111111 is a deficient number, since it is larger than the sum of its proper divisors (7153831283433).

21111102111111 is a wasteful number, since it uses less digits than its factorization.

21111102111111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29199311601.

The product of its (nonzero) digits is 4, while the sum is 15.

Adding to 21111102111111 its reverse (11111120111112), we get a palindrome (32222222222223).

The spelling of 21111102111111 in words is "twenty-one trillion, one hundred eleven billion, one hundred two million, one hundred eleven thousand, one hundred eleven".