21226232320 has 80 divisors (see below), whose sum is σ = 50937052320. Its totient is φ = 8483180544.

The previous prime is 21226232267. The next prime is 21226232333. The reversal of 21226232320 is 2323262212.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×21226232320² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3732199 + ... + 3737881.

It is an arithmetic number, because the mean of its divisors is an integer number (636713154).

Almost surely, 2^21226232320 is an apocalyptic number.

21226232320 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 21226232320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25468526160).

21226232320 is an abundant number, since it is smaller than the sum of its proper divisors (29710820000).

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

21226232320 is an equidigital number, since it uses as much as digits as its factorization.

21226232320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7165 (or 7149 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 21226232320 its reverse (2323262212), we get a palindrome (23549494532).

The spelling of 21226232320 in words is "twenty-one billion, two hundred twenty-six million, two hundred thirty-two thousand, three hundred twenty".