666056 has 8 divisors (see below), whose sum is σ = 1248870. Its totient is φ = 333024.

The previous prime is 666041. The next prime is 666067. The reversal of 666056 is 650666.

It can be written as a sum of positive squares in only one way, i.e., 448900 + 217156 = 670^2 + 466^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

666056 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 as a sum of consecutive naturals, namely, 41621 + ... + 41636.

2⁶⁶⁶⁰⁵⁶ is an apocalyptic number.

It is an amenable number.

666056 is a deficient number, since it is larger than the sum of its proper divisors (582814).

666056 is a wasteful number, since it uses less digits than its factorization.

666056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83263 (or 83259 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 666056 is about 816.1225398186. The cubic root of 666056 is about 87.3313650017.

The spelling of 666056 in words is "six hundred sixty-six thousand, fifty-six".