21320451360 has 288 divisors, whose sum is σ = 78505867440. Its totient is φ = 5237858304.

The previous prime is 21320451353. The next prime is 21320451389. The reversal of 21320451360 is 6315402312.

It can be written as a sum of positive squares in 8 ways, for example, as 1307256336 + 20013195024 = 36156^2 + 141468^2 .

It is a tau number, because it is divible by the number of its divisors (288).

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, 14919126 + ... + 14920554.

Almost surely, 2^21320451360 is an apocalyptic number.

21320451360 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 21320451360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39252933720).

21320451360 is an abundant number, since it is smaller than the sum of its proper divisors (57185416080).

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

21320451360 is a wasteful number, since it uses less digits than its factorization.

21320451360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2260 (or 2249 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

Adding to 21320451360 its reverse (6315402312), we get a palindrome (27635853672).

The spelling of 21320451360 in words is "twenty-one billion, three hundred twenty million, four hundred fifty-one thousand, three hundred sixty".