21123312223 has 8 divisors (see below), whose sum is σ = 22800724688. Its totient is φ = 19453405824.

The previous prime is 21123312167. The next prime is 21123312229. The reversal of 21123312223 is 32221332112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21123312223 - 2²⁵ = 21089757791 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21123312194 and 21123312203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123312229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1870665 + ... + 1881922.

It is an arithmetic number, because the mean of its divisors is an integer number (2850090586).

Almost surely, 2^21123312223 is an apocalyptic number.

21123312223 is a deficient number, since it is larger than the sum of its proper divisors (1677412465).

21123312223 is a wasteful number, since it uses less digits than its factorization.

21123312223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3753033.

The product of its digits is 864, while the sum is 22.

Adding to 21123312223 its reverse (32221332112), we get a palindrome (53344644335).

The spelling of 21123312223 in words is "twenty-one billion, one hundred twenty-three million, three hundred twelve thousand, two hundred twenty-three".