665625 has 24 divisors (see below), whose sum is σ = 1124928. Its totient is φ = 350000.

The previous prime is 665617. The next prime is 665629. The reversal of 665625 is 526566.

It is not a de Polignac number, because 665625 - 2³ = 665617 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 665592 and 665601.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 665625.

It is not an unprimeable number, because it can be changed into a prime (665629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9340 + ... + 9410.

It is an arithmetic number, because the mean of its divisors is an integer number (46872).

2⁶⁶⁵⁶²⁵ is an apocalyptic number.

It is an amenable number.

665625 is a deficient number, since it is larger than the sum of its proper divisors (459303).

665625 is an frugal number, since it uses more digits than its factorization.

665625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99 (or 79 counting only the distinct ones).

The product of its digits is 10800, while the sum is 30.

The square root of 665625 is about 815.8584436040. The cubic root of 665625 is about 87.3125237731.

The spelling of 665625 in words is "six hundred sixty-five thousand, six hundred twenty-five".