523665 has 24 divisors (see below), whose sum is σ = 943488. Its totient is φ = 278640.

The previous prime is 523657. The next prime is 523667. The reversal of 523665 is 566325.

It is not a de Polignac number, because 523665 - 2³ = 523657 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nialpdrome in base 9.

It is not an unprimeable number, because it can be changed into a prime (523667) 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, 1000 + ... + 1430.

It is an arithmetic number, because the mean of its divisors is an integer number (39312).

523665 is a Friedman number, since it can be written as (3*(5-2))^6-6^5, using all its digits and the basic arithmetic operations.

2⁵²³⁶⁶⁵ is an apocalyptic number.

It is an amenable number.

523665 is a deficient number, since it is larger than the sum of its proper divisors (419823).

523665 is an equidigital number, since it uses as much as digits as its factorization.

523665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451 (or 439 counting only the distinct ones).

The product of its digits is 5400, while the sum is 27.

The square root of 523665 is about 723.6470133981. The cubic root of 523665 is about 80.6029956176.

The spelling of 523665 in words is "five hundred twenty-three thousand, six hundred sixty-five".