665535 has 16 divisors (see below), whose sum is σ = 1147104. Its totient is φ = 327552.

The previous prime is 665527. The next prime is 665549. The reversal of 665535 is 535566.

It is not a de Polignac number, because 665535 - 2³ = 665527 is a prime.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1512 + ... + 1901.

It is an arithmetic number, because the mean of its divisors is an integer number (71694).

2⁶⁶⁵⁵³⁵ is an apocalyptic number.

665535 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

665535 is a deficient number, since it is larger than the sum of its proper divisors (481569).

665535 is a wasteful number, since it uses less digits than its factorization.

665535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3434.

The product of its digits is 13500, while the sum is 30.

The square root of 665535 is about 815.8032851123. The cubic root of 665535 is about 87.3085883834.

The spelling of 665535 in words is "six hundred sixty-five thousand, five hundred thirty-five".