40665 has 8 divisors (see below), whose sum is σ = 65088. Its totient is φ = 21680.

The previous prime is 40639. The next prime is 40693. The reversal of 40665 is 56604.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 40665 - 2⁹ = 40153 is a prime.

It is a Curzon number.

40665 is a lucky number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 40665.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1341 + ... + 1370.

It is an arithmetic number, because the mean of its divisors is an integer number (8136).

2⁴⁰⁶⁶⁵ is an apocalyptic number.

It is an amenable number.

40665 is a deficient number, since it is larger than the sum of its proper divisors (24423).

40665 is a wasteful number, since it uses less digits than its factorization.

40665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2719.

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 40665 is about 201.6556470819. The cubic root of 40665 is about 34.3880005922.

The spelling of 40665 in words is "forty thousand, six hundred sixty-five".