665249 has 8 divisors (see below), whose sum is σ = 727272. Its totient is φ = 604800.

The previous prime is 665239. The next prime is 665251. The reversal of 665249 is 942566.

It can be written as a sum of positive squares in 4 ways, for example, as 117649 + 547600 = 343^2 + 740^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 665249 - 2⁴ = 665233 is a prime.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 665249.

It is not an unprimeable number, because it can be changed into a prime (665239) 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, 599 + ... + 1299.

It is an arithmetic number, because the mean of its divisors is an integer number (90909).

2⁶⁶⁵²⁴⁹ is an apocalyptic number.

It is an amenable number.

665249 is a deficient number, since it is larger than the sum of its proper divisors (62023).

665249 is a wasteful number, since it uses less digits than its factorization.

665249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 787.

The product of its digits is 12960, while the sum is 32.

The square root of 665249 is about 815.6279789218. The cubic root of 665249 is about 87.2960802338.

Adding to 665249 its sum of digits (32), we get a triangular number (665281 = T₁₁₅₃).

The spelling of 665249 in words is "six hundred sixty-five thousand, two hundred forty-nine".