665231 has 12 divisors (see below), whose sum is σ = 794352. Its totient is φ = 545664.

The previous prime is 665221. The next prime is 665233. The reversal of 665231 is 132566.

665231 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-665231 is a prime.

It is a super-2 number, since 2×665231² = 885064566722, which contains 22 as substring.

It is a hoax number, since the sum of its digits (23) coincides with the sum of the digits of its distinct prime factors.

It is a d-powerful number, because it can be written as 6⁴ + 6⁴ + 2¹⁷ + 5³ + 3¹² + 1 .

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 665197 and 665206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665233) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5831 + ... + 5943.

It is an arithmetic number, because the mean of its divisors is an integer number (66196).

2⁶⁶⁵²³¹ is an apocalyptic number.

665231 is a deficient number, since it is larger than the sum of its proper divisors (129121).

665231 is a wasteful number, since it uses less digits than its factorization.

665231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178 (or 149 counting only the distinct ones).

The product of its digits is 1080, while the sum is 23.

The square root of 665231 is about 815.6169444047. The cubic root of 665231 is about 87.2952928877.

Adding to 665231 its reverse (132566), we get a palindrome (797797).

The spelling of 665231 in words is "six hundred sixty-five thousand, two hundred thirty-one".