56166550565 has 4 divisors (see below), whose sum is σ = 67399860684. Its totient is φ = 44933240448.

The previous prime is 56166550553. The next prime is 56166550571. The reversal of 56166550565 is 56505566165.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56505566165 = 5 ⋅11301113233.

It can be written as a sum of positive squares in 2 ways, for example, as 28007361316 + 28159189249 = 167354^2 + 167807^2 .

It is a cyclic number.

It is not a de Polignac number, because 56166550565 - 2⁴ = 56166550549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5616655052 + ... + 5616655061.

It is an arithmetic number, because the mean of its divisors is an integer number (16849965171).

Almost surely, 2^56166550565 is an apocalyptic number.

It is an amenable number.

56166550565 is a deficient number, since it is larger than the sum of its proper divisors (11233310119).

56166550565 is a wasteful number, since it uses less digits than its factorization.

56166550565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11233310118.

The product of its (nonzero) digits is 4050000, while the sum is 50.

The spelling of 56166550565 in words is "fifty-six billion, one hundred sixty-six million, five hundred fifty thousand, five hundred sixty-five".