665056 has 24 divisors (see below), whose sum is σ = 1496880. Its totient is φ = 284928.

The previous prime is 665053. The next prime is 665069. The reversal of 665056 is 650566.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1261 + ... + 1708.

It is an arithmetic number, because the mean of its divisors is an integer number (62370).

2⁶⁶⁵⁰⁵⁶ is an apocalyptic number.

It is an amenable number.

665056 is an abundant number, since it is smaller than the sum of its proper divisors (831824).

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

665056 is a wasteful number, since it uses less digits than its factorization.

665056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2986 (or 2978 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 28.

The square root of 665056 is about 815.5096565952. The cubic root of 665056 is about 87.2876373936.

The spelling of 665056 in words is "six hundred sixty-five thousand, fifty-six".