21586725504 has 320 divisors, whose sum is σ = 67772390400. Its totient is φ = 6810531840.

The previous prime is 21586725491. The next prime is 21586725521. The reversal of 21586725504 is 40552768512.

21586725504 is a `hidden beast` number, since 2 + 15 + 86 + 7 + 2 + 550 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21586725504.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 15105462 + ... + 15106890.

It is an arithmetic number, because the mean of its divisors is an integer number (211788720).

Almost surely, 2^21586725504 is an apocalyptic number.

21586725504 is a gapful number since it is divisible by the number (24) 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 21586725504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33886195200).

21586725504 is an abundant number, since it is smaller than the sum of its proper divisors (46185664896).

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

21586725504 is a wasteful number, since it uses less digits than its factorization.

21586725504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1533 (or 1512 counting only the distinct ones).

The product of its (nonzero) digits is 672000, while the sum is 45.

The spelling of 21586725504 in words is "twenty-one billion, five hundred eighty-six million, seven hundred twenty-five thousand, five hundred four".