665595 has 24 divisors (see below), whose sum is σ = 1319136. Its totient is φ = 304128.

The previous prime is 665591. The next prime is 665603. The reversal of 665595 is 595566.

665595 is a `hidden beast` number, since 6 + 65 + 595 = 666.

It is not a de Polignac number, because 665595 - 2² = 665591 is a prime.

It is an Ulam number.

665595 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (665591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 742 + ... + 1371.

It is an arithmetic number, because the mean of its divisors is an integer number (54964).

2⁶⁶⁵⁵⁹⁵ is an apocalyptic number.

665595 is a deficient number, since it is larger than the sum of its proper divisors (653541).

665595 is a wasteful number, since it uses less digits than its factorization.

665595 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2131 (or 2128 counting only the distinct ones).

The product of its digits is 40500, while the sum is 36.

The square root of 665595 is about 815.8400578545. The cubic root of 665595 is about 87.3112120160.

It can be divided in two parts, 66559 and 5, that added together give a square (66564 = 258²).

The spelling of 665595 in words is "six hundred sixty-five thousand, five hundred ninety-five".