21234022321 has 4 divisors (see below), whose sum is σ = 21234391552. Its totient is φ = 21233653092.

The previous prime is 21234022309. The next prime is 21234022357. The reversal of 21234022321 is 12322043212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21234022321 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21234022292 and 21234022301.

It is not an unprimeable number, because it can be changed into a prime (21234022391) 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, 77721 + ... + 220246.

It is an arithmetic number, because the mean of its divisors is an integer number (5308597888).

Almost surely, 2^21234022321 is an apocalyptic number.

It is an amenable number.

21234022321 is a deficient number, since it is larger than the sum of its proper divisors (369231).

21234022321 is an equidigital number, since it uses as much as digits as its factorization.

21234022321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 369230.

The product of its (nonzero) digits is 1152, while the sum is 22.

Adding to 21234022321 its reverse (12322043212), we get a palindrome (33556065533).

The spelling of 21234022321 in words is "twenty-one billion, two hundred thirty-four million, twenty-two thousand, three hundred twenty-one".