21002110111 has 8 divisors (see below), whose sum is σ = 21068208144. Its totient is φ = 20936044800.

The previous prime is 21002110069. The next prime is 21002110139. The reversal of 21002110111 is 11101120012.

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 21002110111 - 2¹⁹ = 21001585823 is a prime.

It is a super-2 number, since 2×21002110111² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002110141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2116261 + ... + 2126161.

It is an arithmetic number, because the mean of its divisors is an integer number (2633526018).

Almost surely, 2^21002110111 is an apocalyptic number.

21002110111 is a deficient number, since it is larger than the sum of its proper divisors (66098033).

21002110111 is an equidigital number, since it uses as much as digits as its factorization.

21002110111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16361.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21002110111 its reverse (11101120012), we get a palindrome (32103230123).

Subtracting from 21002110111 its reverse (11101120012), we obtain a palindrome (9900990099).

The spelling of 21002110111 in words is "twenty-one billion, two million, one hundred ten thousand, one hundred eleven".