21101012021111 has 16 divisors (see below), whose sum is σ = 23123523886848. Its totient is φ = 19095893865600.

The previous prime is 21101012021081. The next prime is 21101012021129. The reversal of 21101012021111 is 11112021010112.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21101012021111 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101012021711) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20039471 + ... + 21066143.

It is an arithmetic number, because the mean of its divisors is an integer number (1445220242928).

Almost surely, 2^{21101012021111} is an apocalyptic number.

21101012021111 is a deficient number, since it is larger than the sum of its proper divisors (2022511865737).

21101012021111 is a wasteful number, since it uses less digits than its factorization.

21101012021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1035142.

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

Adding to 21101012021111 its reverse (11112021010112), we get a palindrome (32213033031223).

The spelling of 21101012021111 in words is "twenty-one trillion, one hundred one billion, twelve million, twenty-one thousand, one hundred eleven".