66065985 has 24 divisors (see below), whose sum is σ = 115024104. Its totient is φ = 35078400.

The previous prime is 66065977. The next prime is 66066043. The reversal of 66065985 is 58956066.

It can be written as a sum of positive squares in 4 ways, for example, as 3196944 + 62869041 = 1788^2 + 7929^2 .

It is not a de Polignac number, because 66065985 - 2³ = 66065977 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 66065985.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7335 + ... + 13635.

It is an arithmetic number, because the mean of its divisors is an integer number (4792671).

Almost surely, 2^66065985 is an apocalyptic number.

It is an amenable number.

66065985 is a deficient number, since it is larger than the sum of its proper divisors (48958119).

66065985 is a wasteful number, since it uses less digits than its factorization.

66065985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6545 (or 6542 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The square root of 66065985 is about 8128.0984861159. The cubic root of 66065985 is about 404.2586345901.

The spelling of 66065985 in words is "sixty-six million, sixty-five thousand, nine hundred eighty-five".