21102111023 has 6 divisors (see below), whose sum is σ = 24547353696. Its totient is φ = 18087523692.

The previous prime is 21102111011. The next prime is 21102111031. The reversal of 21102111023 is 32011120112.

It is not a de Polignac number, because 21102111023 - 2⁴ = 21102111007 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21102110989 and 21102111007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102111053) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 215327615 + ... + 215327712.

It is an arithmetic number, because the mean of its divisors is an integer number (4091225616).

Almost surely, 2^21102111023 is an apocalyptic number.

21102111023 is a deficient number, since it is larger than the sum of its proper divisors (3445242673).

21102111023 is an equidigital number, since it uses as much as digits as its factorization.

21102111023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430655341 (or 430655334 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21102111023 its reverse (32011120112), we get a palindrome (53113231135).

The spelling of 21102111023 in words is "twenty-one billion, one hundred two million, one hundred eleven thousand, twenty-three".