665849 has 8 divisors (see below), whose sum is σ = 703488. Its totient is φ = 629280.

The previous prime is 665843. The next prime is 665857. The reversal of 665849 is 948566.

665849 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-665849 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (665843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1229 + ... + 1685.

It is an arithmetic number, because the mean of its divisors is an integer number (87936).

2⁶⁶⁵⁸⁴⁹ is an apocalyptic number.

It is an amenable number.

665849 is a deficient number, since it is larger than the sum of its proper divisors (37639).

665849 is a wasteful number, since it uses less digits than its factorization.

665849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 535.

The product of its digits is 51840, while the sum is 38.

The square root of 665849 is about 815.9957107730. The cubic root of 665849 is about 87.3223169809.

The spelling of 665849 in words is "six hundred sixty-five thousand, eight hundred forty-nine".