21331111223 has 4 divisors (see below), whose sum is σ = 21570786720. Its totient is φ = 21091435728.

The previous prime is 21331111213. The next prime is 21331111261. The reversal of 21331111223 is 32211113312.

It is a happy number.

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 21331111223 - 2⁸ = 21331110967 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21331111195 and 21331111204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21331111213) 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, 119837615 + ... + 119837792.

It is an arithmetic number, because the mean of its divisors is an integer number (5392696680).

Almost surely, 2^21331111223 is an apocalyptic number.

21331111223 is a deficient number, since it is larger than the sum of its proper divisors (239675497).

21331111223 is an equidigital number, since it uses as much as digits as its factorization.

21331111223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239675496.

The product of its digits is 216, while the sum is 20.

Adding to 21331111223 its reverse (32211113312), we get a palindrome (53542224535).

The spelling of 21331111223 in words is "twenty-one billion, three hundred thirty-one million, one hundred eleven thousand, two hundred twenty-three".