665205 has 16 divisors (see below), whose sum is σ = 1083264. Its totient is φ = 348480.

The previous prime is 665201. The next prime is 665207. The reversal of 665205 is 502566.

665205 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 665205 - 2² = 665201 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 552 + ... + 1278.

It is an arithmetic number, because the mean of its divisors is an integer number (67704).

2⁶⁶⁵²⁰⁵ is an apocalyptic number.

It is an amenable number.

665205 is a deficient number, since it is larger than the sum of its proper divisors (418059).

665205 is a wasteful number, since it uses less digits than its factorization.

665205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 796.

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 665205 is about 815.6010053942. The cubic root of 665205 is about 87.2941555850.

The spelling of 665205 in words is "six hundred sixty-five thousand, two hundred five".