21323230320 has 240 divisors, whose sum is σ = 79732753920. Its totient is φ = 4617229824.

The previous prime is 21323230319. The next prime is 21323230363. The reversal of 21323230320 is 2303232312.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 588901 + ... + 624059.

It is an arithmetic number, because the mean of its divisors is an integer number (332219808).

Almost surely, 2^21323230320 is an apocalyptic number.

21323230320 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 21323230320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39866376960).

21323230320 is an abundant number, since it is smaller than the sum of its proper divisors (58409523600).

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

21323230320 is a wasteful number, since it uses less digits than its factorization.

21323230320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35220 (or 35195 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 21.

Adding to 21323230320 its reverse (2303232312), we get a palindrome (23626462632).

The spelling of 21323230320 in words is "twenty-one billion, three hundred twenty-three million, two hundred thirty thousand, three hundred twenty".