666980 has 12 divisors (see below), whose sum is σ = 1400700. Its totient is φ = 266784.

The previous prime is 666979. The next prime is 666983. The reversal of 666980 is 89666.

It can be written as a sum of positive squares in 2 ways, for example, as 487204 + 179776 = 698^2 + 424^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 666980.

It is not an unprimeable number, because it can be changed into a prime (666983) 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, 16655 + ... + 16694.

It is an arithmetic number, because the mean of its divisors is an integer number (116725).

2⁶⁶⁶⁹⁸⁰ is an apocalyptic number.

It is an amenable number.

666980 is an abundant number, since it is smaller than the sum of its proper divisors (733720).

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

666980 is a wasteful number, since it uses less digits than its factorization.

666980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33358 (or 33356 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 666980 is about 816.6884350840. The cubic root of 666980 is about 87.3717304240.

The spelling of 666980 in words is "six hundred sixty-six thousand, nine hundred eighty".