666065 has 4 divisors (see below), whose sum is σ = 799284. Its totient is φ = 532848.

The previous prime is 666041. The next prime is 666067. The reversal of 666065 is 560666.

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 473344 + 192721 = 688^2 + 439^2 .

It is a cyclic number.

It is not a de Polignac number, because 666065 - 2¹⁶ = 600529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666067) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66602 + ... + 66611.

It is an arithmetic number, because the mean of its divisors is an integer number (199821).

2⁶⁶⁶⁰⁶⁵ is an apocalyptic number.

It is an amenable number.

666065 is a deficient number, since it is larger than the sum of its proper divisors (133219).

666065 is a wasteful number, since it uses less digits than its factorization.

666065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133218.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 666065 is about 816.1280536779. The cubic root of 666065 is about 87.3317583514.

The spelling of 666065 in words is "six hundred sixty-six thousand, sixty-five".