15561065536 has 63 divisors (see below), whose sum is σ = 31970777943. Its totient is φ = 7514578560.

The previous prime is 15561065497. The next prime is 15561065551. The reversal of 15561065536 is 63556016551.

It is a happy number.

The square root of 15561065536 is 124744.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 15561065492 and 15561065501.

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 8 ways as a sum of consecutive naturals, for example, 30936261 + ... + 30936763.

Almost surely, 2^15561065536 is an apocalyptic number.

15561065536 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

15561065536 is the 124744-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15561065536

15561065536 is an abundant number, since it is smaller than the sum of its proper divisors (16409712407).

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

15561065536 is an frugal number, since it uses more digits than its factorization.

15561065536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1080 (or 536 counting only the distinct ones).

The product of its (nonzero) digits is 405000, while the sum is 43.

The spelling of 15561065536 in words is "fifteen billion, five hundred sixty-one million, sixty-five thousand, five hundred thirty-six".