21312332323 has 4 divisors (see below), whose sum is σ = 21330533608. Its totient is φ = 21294131040.

The previous prime is 21312332309. The next prime is 21312332333. The reversal of 21312332323 is 32323321312.

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-21312332323 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21312332333) 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, 9098886 + ... + 9101227.

It is an arithmetic number, because the mean of its divisors is an integer number (5332633402).

Almost surely, 2^21312332323 is an apocalyptic number.

21312332323 is a deficient number, since it is larger than the sum of its proper divisors (18201285).

21312332323 is a wasteful number, since it uses less digits than its factorization.

21312332323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18201284.

The product of its digits is 3888, while the sum is 25.

Adding to 21312332323 its reverse (32323321312), we get a palindrome (53635653635).

The spelling of 21312332323 in words is "twenty-one billion, three hundred twelve million, three hundred thirty-two thousand, three hundred twenty-three".