66550566050665 has 4 divisors (see below), whose sum is σ = 79860679260804. Its totient is φ = 53240452840528.

The previous prime is 66550566050659. The next prime is 66550566050699. The reversal of 66550566050665 is 56605066505566.

66550566050665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 49406461434729 + 17144104615936 = 7028973^2 + 4140544^2 .

It is a cyclic number.

It is not a de Polignac number, because 66550566050665 - 2⁷ = 66550566050537 is a prime.

It is a Duffinian 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 3 ways as a sum of consecutive naturals, for example, 6655056605062 + ... + 6655056605071.

It is an arithmetic number, because the mean of its divisors is an integer number (19965169815201).

Almost surely, 2^{66550566050665} is an apocalyptic number.

It is an amenable number.

66550566050665 is a deficient number, since it is larger than the sum of its proper divisors (13310113210139).

66550566050665 is a wasteful number, since it uses less digits than its factorization.

66550566050665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13310113210138.

The product of its (nonzero) digits is 145800000, while the sum is 61.

The spelling of 66550566050665 in words is "sixty-six trillion, five hundred fifty billion, five hundred sixty-six million, fifty thousand, six hundred sixty-five".