21112708823 has 4 divisors (see below), whose sum is σ = 21242234808. Its totient is φ = 20983182840.

The previous prime is 21112708777. The next prime is 21112708829. The reversal of 21112708823 is 32880721112.

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 21112708823 - 2⁶ = 21112708759 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112708829) 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, 64762748 + ... + 64763073.

It is an arithmetic number, because the mean of its divisors is an integer number (5310558702).

Almost surely, 2^21112708823 is an apocalyptic number.

21112708823 is a deficient number, since it is larger than the sum of its proper divisors (129525985).

21112708823 is a wasteful number, since it uses less digits than its factorization.

21112708823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129525984.

The product of its (nonzero) digits is 10752, while the sum is 35.

The spelling of 21112708823 in words is "twenty-one billion, one hundred twelve million, seven hundred eight thousand, eight hundred twenty-three".