21110522423 has 4 divisors (see below), whose sum is σ = 22028371248. Its totient is φ = 20192673600.

The previous prime is 21110522351. The next prime is 21110522443. The reversal of 21110522423 is 32422501112.

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-21110522423 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23), and also a Moran number because the ratio is a prime number: 917848801 = 21110522423 / (2 + 1 + 1 + 1 + 0 + 5 + 2 + 2 + 4 + 2 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110522443) 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, 458924378 + ... + 458924423.

It is an arithmetic number, because the mean of its divisors is an integer number (5507092812).

Almost surely, 2^21110522423 is an apocalyptic number.

21110522423 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21110522423 is a deficient number, since it is larger than the sum of its proper divisors (917848825).

21110522423 is an equidigital number, since it uses as much as digits as its factorization.

21110522423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 917848824.

The product of its (nonzero) digits is 960, while the sum is 23.

The spelling of 21110522423 in words is "twenty-one billion, one hundred ten million, five hundred twenty-two thousand, four hundred twenty-three".