561566042865 has 24 divisors (see below), whose sum is σ = 974298642408. Its totient is φ = 299219581440.

The previous prime is 561566042839. The next prime is 561566042879. The reversal of 561566042865 is 568240665165.

561566042865 is a `hidden beast` number, since 5 + 6 + 1 + 5 + 6 + 604 + 28 + 6 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 149852603664 + 411713439201 = 387108^2 + 641649^2 .

It is not a de Polignac number, because 561566042865 - 2⁵ = 561566042833 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5833144 + ... + 5928633.

It is an arithmetic number, because the mean of its divisors is an integer number (40595776767).

Almost surely, 2^561566042865 is an apocalyptic number.

It is an amenable number.

561566042865 is a deficient number, since it is larger than the sum of its proper divisors (412732599543).

561566042865 is a wasteful number, since it uses less digits than its factorization.

561566042865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11762849 (or 11762846 counting only the distinct ones).

The product of its (nonzero) digits is 10368000, while the sum is 54.

The spelling of 561566042865 in words is "five hundred sixty-one billion, five hundred sixty-six million, forty-two thousand, eight hundred sixty-five".