665288 has 16 divisors (see below), whose sum is σ = 1343580. Its totient is φ = 307008.

The previous prime is 665279. The next prime is 665293. The reversal of 665288 is 882566.

It can be written as a sum of positive squares in 2 ways, for example, as 487204 + 178084 = 698^2 + 422^2 .

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

665288 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3095 + ... + 3302.

2⁶⁶⁵²⁸⁸ is an apocalyptic number.

It is an amenable number.

665288 is an abundant number, since it is smaller than the sum of its proper divisors (678292).

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

665288 is a wasteful number, since it uses less digits than its factorization.

665288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6416 (or 6412 counting only the distinct ones).

The product of its digits is 23040, while the sum is 35.

The square root of 665288 is about 815.6518865300. The cubic root of 665288 is about 87.2977861017.

The spelling of 665288 in words is "six hundred sixty-five thousand, two hundred eighty-eight".