665707 has 4 divisors (see below), whose sum is σ = 760816. Its totient is φ = 570600.

The previous prime is 665677. The next prime is 665713. The reversal of 665707 is 707566.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 707566 = 2 ⋅353783.

It is a cyclic number.

It is not a de Polignac number, because 665707 - 2¹¹ = 663659 is a prime.

It is not an unprimeable number, because it can be changed into a prime (665747) 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, 47544 + ... + 47557.

It is an arithmetic number, because the mean of its divisors is an integer number (190204).

2⁶⁶⁵⁷⁰⁷ is an apocalyptic number.

665707 is a deficient number, since it is larger than the sum of its proper divisors (95109).

665707 is an equidigital number, since it uses as much as digits as its factorization.

665707 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95108.

The product of its (nonzero) digits is 8820, while the sum is 31.

The square root of 665707 is about 815.9086958723. The cubic root of 665707 is about 87.3161090416.

The spelling of 665707 in words is "six hundred sixty-five thousand, seven hundred seven".