21001110021111 has 8 divisors (see below), whose sum is σ = 30547069121664. Its totient is φ = 12727945467320.

The previous prime is 21001110021107. The next prime is 21001110021233. The reversal of 21001110021111 is 11112001110012.

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 21001110021111 - 2² = 21001110021107 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001110026111) 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, 318198636651 + ... + 318198636716.

It is an arithmetic number, because the mean of its divisors is an integer number (3818383640208).

Almost surely, 2^{21001110021111} is an apocalyptic number.

21001110021111 is a deficient number, since it is larger than the sum of its proper divisors (9545959100553).

21001110021111 is a wasteful number, since it uses less digits than its factorization.

21001110021111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 636397273381.

The product of its (nonzero) digits is 4, while the sum is 12.

Adding to 21001110021111 its reverse (11112001110012), we get a palindrome (32113111131123).

The spelling of 21001110021111 in words is "twenty-one trillion, one billion, one hundred ten million, twenty-one thousand, one hundred eleven".