21231222323 has 4 divisors (see below), whose sum is σ = 21231513888. Its totient is φ = 21230930760.

The previous prime is 21231222319. The next prime is 21231222359. The reversal of 21231222323 is 32322213212.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21231222323 - 2² = 21231222319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21231242323) 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, 65990 + ... + 216372.

It is an arithmetic number, because the mean of its divisors is an integer number (5307878472).

Almost surely, 2^21231222323 is an apocalyptic number.

21231222323 is a deficient number, since it is larger than the sum of its proper divisors (291565).

21231222323 is a wasteful number, since it uses less digits than its factorization.

21231222323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 291564.

The product of its digits is 1728, while the sum is 23.

Adding to 21231222323 its reverse (32322213212), we get a palindrome (53553435535).

The spelling of 21231222323 in words is "twenty-one billion, two hundred thirty-one million, two hundred twenty-two thousand, three hundred twenty-three".