21323122320 has 160 divisors (see below), whose sum is σ = 68591502720. Its totient is φ = 5473198080.

The previous prime is 21323122309. The next prime is 21323122351. The reversal of 21323122320 is 2322132312.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2340975 + ... + 2350065.

It is an arithmetic number, because the mean of its divisors is an integer number (428696892).

Almost surely, 2^21323122320 is an apocalyptic number.

21323122320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21323122320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34295751360).

21323122320 is an abundant number, since it is smaller than the sum of its proper divisors (47268380400).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21323122320 is a wasteful number, since it uses less digits than its factorization.

21323122320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9473 (or 9467 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 21323122320 its reverse (2322132312), we get a palindrome (23645254632).

The spelling of 21323122320 in words is "twenty-one billion, three hundred twenty-three million, one hundred twenty-two thousand, three hundred twenty".