660979 has 4 divisors (see below), whose sum is σ = 721080. Its totient is φ = 600880.

The previous prime is 660973. The next prime is 660983. The reversal of 660979 is 979066.

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 660979 - 2⁷ = 660851 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (660973) 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 3 ways as a sum of consecutive naturals, for example, 30034 + ... + 30055.

It is an arithmetic number, because the mean of its divisors is an integer number (180270).

2⁶⁶⁰⁹⁷⁹ is an apocalyptic number.

660979 is a deficient number, since it is larger than the sum of its proper divisors (60101).

660979 is a wasteful number, since it uses less digits than its factorization.

660979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60100.

The product of its (nonzero) digits is 20412, while the sum is 37.

The square root of 660979 is about 813.0061500382. The cubic root of 660979 is about 87.1089048829.

The spelling of 660979 in words is "six hundred sixty thousand, nine hundred seventy-nine".