21579816960 has 896 divisors, whose sum is σ = 88075008000. Its totient is φ = 4968677376.

The previous prime is 21579816913. The next prime is 21579816967. The reversal of 21579816960 is 6961897512.

21579816960 is a `hidden beast` number, since 2 + 1 + 579 + 8 + 1 + 6 + 9 + 60 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 21579816897 and 21579816906.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21579816967) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 273162201 + ... + 273162279.

It is an arithmetic number, because the mean of its divisors is an integer number (98298000).

Almost surely, 2^21579816960 is an apocalyptic number.

21579816960 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 21579816960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44037504000).

21579816960 is an abundant number, since it is smaller than the sum of its proper divisors (66495191040).

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

21579816960 is a wasteful number, since it uses less digits than its factorization.

21579816960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151 (or 121 counting only the distinct ones).

The product of its (nonzero) digits is 1632960, while the sum is 54.

The spelling of 21579816960 in words is "twenty-one billion, five hundred seventy-nine million, eight hundred sixteen thousand, nine hundred sixty".