408999 has 4 divisors (see below), whose sum is σ = 545336. Its totient is φ = 272664.

The previous prime is 408997. The next prime is 409007. The reversal of 408999 is 999804.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 408999 - 2¹ = 408997 is a prime.

It is a D-number.

It is a Duffinian number.

408999 is a modest number, since divided by 999 gives 408 as remainder.

408999 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (408997) 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, 68164 + ... + 68169.

It is an arithmetic number, because the mean of its divisors is an integer number (136334).

2⁴⁰⁸⁹⁹⁹ is an apocalyptic number.

408999 is a deficient number, since it is larger than the sum of its proper divisors (136337).

408999 is a wasteful number, since it uses less digits than its factorization.

408999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136336.

The product of its (nonzero) digits is 23328, while the sum is 39.

The square root of 408999 is about 639.5302963895. The cubic root of 408999 is about 74.2290807079.

The spelling of 408999 in words is "four hundred eight thousand, nine hundred ninety-nine".