21311223323 has 4 divisors (see below), whose sum is σ = 22950548208. Its totient is φ = 19671898440.

The previous prime is 21311223257. The next prime is 21311223397. The reversal of 21311223323 is 32332211312.

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 21311223323 - 2¹⁰ = 21311222299 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21311223223) 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, 819662423 + ... + 819662448.

It is an arithmetic number, because the mean of its divisors is an integer number (5737637052).

Almost surely, 2^21311223323 is an apocalyptic number.

21311223323 is a deficient number, since it is larger than the sum of its proper divisors (1639324885).

21311223323 is a wasteful number, since it uses less digits than its factorization.

21311223323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1639324884.

The product of its digits is 1296, while the sum is 23.

Adding to 21311223323 its reverse (32332211312), we get a palindrome (53643434635).

The spelling of 21311223323 in words is "twenty-one billion, three hundred eleven million, two hundred twenty-three thousand, three hundred twenty-three".