21112111023 has 4 divisors (see below), whose sum is σ = 28149481368. Its totient is φ = 14074740680.

The previous prime is 21112111021. The next prime is 21112111051. The reversal of 21112111023 is 32011121112.

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

It is a cyclic number.

It is not a de Polignac number, because 21112111023 - 2¹ = 21112111021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21112110993 and 21112111011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112111021) 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, 3518685168 + ... + 3518685173.

It is an arithmetic number, because the mean of its divisors is an integer number (7037370342).

Almost surely, 2^21112111023 is an apocalyptic number.

21112111023 is a deficient number, since it is larger than the sum of its proper divisors (7037370345).

21112111023 is an equidigital number, since it uses as much as digits as its factorization.

21112111023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7037370344.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 21112111023 its reverse (32011121112), we get a palindrome (53123232135).

The spelling of 21112111023 in words is "twenty-one billion, one hundred twelve million, one hundred eleven thousand, twenty-three".