231605 has 8 divisors (see below), whose sum is σ = 303264. Its totient is φ = 168400.

The previous prime is 231599. The next prime is 231607. The reversal of 231605 is 506132.

231605 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 not a de Polignac number, because 231605 - 2⁴ = 231589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231607) 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, 2051 + ... + 2160.

It is an arithmetic number, because the mean of its divisors is an integer number (37908).

2²³¹⁶⁰⁵ is an apocalyptic number.

It is an amenable number.

231605 is a deficient number, since it is larger than the sum of its proper divisors (71659).

231605 is a wasteful number, since it uses less digits than its factorization.

231605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4227.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 231605 is about 481.2535714153. The cubic root of 231605 is about 61.4114441421.

Adding to 231605 its reverse (506132), we get a palindrome (737737).

The spelling of 231605 in words is "two hundred thirty-one thousand, six hundred five".