15725638656 has 528 divisors, whose sum is σ = 59227144704. Its totient is φ = 3899916288.

The previous prime is 15725638613. The next prime is 15725638751. The reversal of 15725638656 is 65683652751.

It is a happy number.

15725638656 is a `hidden beast` number, since 1 + 5 + 7 + 256 + 386 + 5 + 6 = 666.

It is a super-2 number, since 2×15725638656² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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, 14256601 + ... + 14257703.

Almost surely, 2^15725638656 is an apocalyptic number.

15725638656 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 15725638656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29613572352).

15725638656 is an abundant number, since it is smaller than the sum of its proper divisors (43501506048).

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

15725638656 is a wasteful number, since it uses less digits than its factorization.

15725638656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1166 (or 1145 counting only the distinct ones).

The product of its digits is 9072000, while the sum is 54.

The spelling of 15725638656 in words is "fifteen billion, seven hundred twenty-five million, six hundred thirty-eight thousand, six hundred fifty-six".