665059 has 4 divisors (see below), whose sum is σ = 667216. Its totient is φ = 662904.

The previous prime is 665053. The next prime is 665069. The reversal of 665059 is 950566.

It is a happy number.

665059 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 950566 = 2 ⋅475283.

It is a cyclic number.

It is not a de Polignac number, because 665059 - 2³ = 665051 is a prime.

It is a Duffinian number.

665059 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 665059.

It is not an unprimeable number, because it can be changed into a prime (665051) 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, 519 + ... + 1264.

It is an arithmetic number, because the mean of its divisors is an integer number (166804).

2⁶⁶⁵⁰⁵⁹ is an apocalyptic number.

665059 is a deficient number, since it is larger than the sum of its proper divisors (2157).

665059 is a wasteful number, since it uses less digits than its factorization.

665059 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2156.

The product of its (nonzero) digits is 8100, while the sum is 31.

The square root of 665059 is about 815.5114959337. The cubic root of 665059 is about 87.2877686420.

The spelling of 665059 in words is "six hundred sixty-five thousand, fifty-nine".