15565314561 has 16 divisors (see below), whose sum is σ = 21661986816. Its totient is φ = 9923005136.

The previous prime is 15565314517. The next prime is 15565314637. The reversal of 15565314561 is 16541356551.

It is a cyclic number.

It is not a de Polignac number, because 15565314561 - 2¹⁵ = 15565281793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (15565314161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 241936 + ... + 299438.

It is an arithmetic number, because the mean of its divisors is an integer number (1353874176).

Almost surely, 2^15565314561 is an apocalyptic number.

It is an amenable number.

15565314561 is a deficient number, since it is larger than the sum of its proper divisors (6096672255).

15565314561 is a wasteful number, since it uses less digits than its factorization.

15565314561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61452.

The product of its digits is 270000, while the sum is 42.

The spelling of 15565314561 in words is "fifteen billion, five hundred sixty-five million, three hundred fourteen thousand, five hundred sixty-one".