666365 has 16 divisors (see below), whose sum is σ = 929280. Its totient is φ = 449280.

The previous prime is 666353. The next prime is 666403. The reversal of 666365 is 563666.

It is not a de Polignac number, because 666365 - 2⁶ = 666301 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2645 + ... + 2885.

It is an arithmetic number, because the mean of its divisors is an integer number (58080).

2⁶⁶⁶³⁶⁵ is an apocalyptic number.

It is an amenable number.

666365 is a deficient number, since it is larger than the sum of its proper divisors (262915).

666365 is a wasteful number, since it uses less digits than its factorization.

666365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332.

The product of its digits is 19440, while the sum is 32.

The square root of 666365 is about 816.3118276737. The cubic root of 666365 is about 87.3448679803.

The spelling of 666365 in words is "six hundred sixty-six thousand, three hundred sixty-five".