365999 has 4 divisors (see below), whose sum is σ = 381936. Its totient is φ = 350064.

The previous prime is 365983. The next prime is 366001. The reversal of 365999 is 999563.

It is a happy number.

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 365999 - 2⁴ = 365983 is a prime.

It is a Duffinian number.

365999 is a modest number, since divided by 999 gives 365 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (365929) 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, 7934 + ... + 7979.

It is an arithmetic number, because the mean of its divisors is an integer number (95484).

2³⁶⁵⁹⁹⁹ is an apocalyptic number.

365999 is a deficient number, since it is larger than the sum of its proper divisors (15937).

365999 is a wasteful number, since it uses less digits than its factorization.

365999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15936.

The product of its digits is 65610, while the sum is 41.

The square root of 365999 is about 604.9785120151. The cubic root of 365999 is about 71.5308358038.

The spelling of 365999 in words is "three hundred sixty-five thousand, nine hundred ninety-nine".