15815725056 has 156 divisors (see below), whose sum is σ = 48373523172. Its totient is φ = 4961599488.

The previous prime is 15815725043. The next prime is 15815725127. The reversal of 15815725056 is 65052751851.

15815725056 is a `hidden beast` number, since 15 + 81 + 57 + 2 + 505 + 6 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 12273094656 + 3542630400 = 110784^2 + 59520^2 .

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 614070 + ... + 639306.

It is an arithmetic number, because the mean of its divisors is an integer number (310086687).

Almost surely, 2^15815725056 is an apocalyptic number.

15815725056 is a gapful number since it is divisible by the number (16) 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 15815725056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24186761586).

15815725056 is an abundant number, since it is smaller than the sum of its proper divisors (32557798116).

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

15815725056 is a wasteful number, since it uses less digits than its factorization.

15815725056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25284 (or 25259 counting only the distinct ones).

The product of its (nonzero) digits is 420000, while the sum is 45.

The spelling of 15815725056 in words is "fifteen billion, eight hundred fifteen million, seven hundred twenty-five thousand, fifty-six".