665960 has 16 divisors (see below), whose sum is σ = 1498500. Its totient is φ = 266368.

The previous prime is 665953. The next prime is 665981. The reversal of 665960 is 69566.

It can be written as a sum of positive squares in 2 ways, for example, as 662596 + 3364 = 814^2 + 58^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8285 + ... + 8364.

2⁶⁶⁵⁹⁶⁰ is an apocalyptic number.

It is an amenable number.

665960 is an abundant number, since it is smaller than the sum of its proper divisors (832540).

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

665960 is a wasteful number, since it uses less digits than its factorization.

665960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16660 (or 16656 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 32.

The square root of 665960 is about 816.0637230021. The cubic root of 665960 is about 87.3271690513.

The spelling of 665960 in words is "six hundred sixty-five thousand, nine hundred sixty".