665748 has 18 divisors (see below), whose sum is σ = 1682954. Its totient is φ = 221904.

The previous prime is 665747. The next prime is 665761. The reversal of 665748 is 847566.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 544644 + 121104 = 738^2 + 348^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 18493 = 665748 / (6 + 6 + 5 + 7 + 4 + 8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665747) 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 5 ways as a sum of consecutive naturals, for example, 9211 + ... + 9282.

2⁶⁶⁵⁷⁴⁸ is an apocalyptic number.

It is an amenable number.

665748 is an abundant number, since it is smaller than the sum of its proper divisors (1017206).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

665748 is a wasteful number, since it uses less digits than its factorization.

665748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18503 (or 18498 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 665748 is about 815.9338208458. The cubic root of 665748 is about 87.3179015654.

The spelling of 665748 in words is "six hundred sixty-five thousand, seven hundred forty-eight".