666874 has 12 divisors (see below), whose sum is σ = 1083726. Its totient is φ = 307632.

The previous prime is 666871. The next prime is 666889. The reversal of 666874 is 478666.

It can be written as a sum of positive squares in 3 ways, for example, as 235225 + 431649 = 485^2 + 657^2 .

It is not an unprimeable number, because it can be changed into a prime (666871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 649 + ... + 1324.

2⁶⁶⁶⁸⁷⁴ is an apocalyptic number.

666874 is a deficient number, since it is larger than the sum of its proper divisors (416852).

666874 is a wasteful number, since it uses less digits than its factorization.

666874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2001 (or 1988 counting only the distinct ones).

The product of its digits is 48384, while the sum is 37.

The square root of 666874 is about 816.6235362760. The cubic root of 666874 is about 87.3671016525.

It can be divided in two parts, 666 and 874, that added together give a triangular number (1540 = T₅₅).

The spelling of 666874 in words is "six hundred sixty-six thousand, eight hundred seventy-four".