66654161665 has 32 divisors (see below), whose sum is σ = 98487760896. Its totient is φ = 42170734080.

The previous prime is 66654161641. The next prime is 66654161767. The reversal of 66654161665 is 56616145666.

It is not a de Polignac number, because 66654161665 - 2¹¹ = 66654159617 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1005744 + ... + 1069966.

It is an arithmetic number, because the mean of its divisors is an integer number (3077742528).

Almost surely, 2^66654161665 is an apocalyptic number.

66654161665 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66654161665 is a deficient number, since it is larger than the sum of its proper divisors (31833599231).

66654161665 is a wasteful number, since it uses less digits than its factorization.

66654161665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66529.

The product of its digits is 4665600, while the sum is 52.

The spelling of 66654161665 in words is "sixty-six billion, six hundred fifty-four million, one hundred sixty-one thousand, six hundred sixty-five".