665716 has 6 divisors (see below), whose sum is σ = 1165010. Its totient is φ = 332856.

The previous prime is 665713. The next prime is 665719. The reversal of 665716 is 617566.

It is an interprime number because it is at equal distance from previous prime (665713) and next prime (665719).

It can be written as a sum of positive squares in only one way, i.e., 624100 + 41616 = 790^2 + 204^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83211 + ... + 83218.

2⁶⁶⁵⁷¹⁶ is an apocalyptic number.

It is an amenable number.

665716 is a deficient number, since it is larger than the sum of its proper divisors (499294).

665716 is a wasteful number, since it uses less digits than its factorization.

665716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166433 (or 166431 counting only the distinct ones).

The product of its digits is 7560, while the sum is 31.

The square root of 665716 is about 815.9142111766. The cubic root of 665716 is about 87.3165025287.

The spelling of 665716 in words is "six hundred sixty-five thousand, seven hundred sixteen".