666884 has 12 divisors (see below), whose sum is σ = 1207500. Its totient is φ = 321888.

The previous prime is 666871. The next prime is 666889. The reversal of 666884 is 488666.

It can be written as a sum of positive squares in 2 ways, for example, as 136900 + 529984 = 370^2 + 728^2 .

It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (666889) 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 3 ways as a sum of consecutive naturals, for example, 2759 + ... + 2990.

It is an arithmetic number, because the mean of its divisors is an integer number (100625).

2⁶⁶⁶⁸⁸⁴ is an apocalyptic number.

It is an amenable number.

666884 is a deficient number, since it is larger than the sum of its proper divisors (540616).

666884 is a wasteful number, since it uses less digits than its factorization.

666884 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5782 (or 5780 counting only the distinct ones).

The product of its digits is 55296, while the sum is 38.

The square root of 666884 is about 816.6296590254. The cubic root of 666884 is about 87.3675383500.

The spelling of 666884 in words is "six hundred sixty-six thousand, eight hundred eighty-four".