660679 has 4 divisors (see below), whose sum is σ = 674784. Its totient is φ = 646576.

The previous prime is 660661. The next prime is 660683. The reversal of 660679 is 976066.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 660679 - 2⁹ = 660167 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660619) 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, 6982 + ... + 7075.

It is an arithmetic number, because the mean of its divisors is an integer number (168696).

2⁶⁶⁰⁶⁷⁹ is an apocalyptic number.

660679 is a deficient number, since it is larger than the sum of its proper divisors (14105).

660679 is a wasteful number, since it uses less digits than its factorization.

660679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14104.

The product of its (nonzero) digits is 13608, while the sum is 34.

The square root of 660679 is about 812.8216286492. The cubic root of 660679 is about 87.0957241182.

The spelling of 660679 in words is "six hundred sixty thousand, six hundred seventy-nine".