665099 has 4 divisors (see below), whose sum is σ = 670464. Its totient is φ = 659736.

The previous prime is 665089. The next prime is 665111. The reversal of 665099 is 990566.

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 665099 - 2⁸ = 664843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665029) 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, 2492 + ... + 2745.

It is an arithmetic number, because the mean of its divisors is an integer number (167616).

2⁶⁶⁵⁰⁹⁹ is an apocalyptic number.

665099 is a deficient number, since it is larger than the sum of its proper divisors (5365).

665099 is a wasteful number, since it uses less digits than its factorization.

665099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5364.

The product of its (nonzero) digits is 14580, while the sum is 35.

The square root of 665099 is about 815.5360200506. The cubic root of 665099 is about 87.2895185823.

The spelling of 665099 in words is "six hundred sixty-five thousand, ninety-nine".