21023000111 has 4 divisors (see below), whose sum is σ = 21023533800. Its totient is φ = 21022466424.

The previous prime is 21023000101. The next prime is 21023000147. The reversal of 21023000111 is 11100032012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21023000111 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21023000092 and 21023000101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21023000101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 202601 + ... + 288258.

It is an arithmetic number, because the mean of its divisors is an integer number (5255883450).

Almost surely, 2^21023000111 is an apocalyptic number.

21023000111 is a deficient number, since it is larger than the sum of its proper divisors (533689).

21023000111 is an equidigital number, since it uses as much as digits as its factorization.

21023000111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 533688.

The product of its (nonzero) digits is 12, while the sum is 11.

Adding to 21023000111 its reverse (11100032012), we get a palindrome (32123032123).

The spelling of 21023000111 in words is "twenty-one billion, twenty-three million, one hundred eleven", and thus it is an aban number.