399806 has 16 divisors (see below), whose sum is σ = 693360. Its totient is φ = 170880.

The previous prime is 399793. The next prime is 399851. The reversal of 399806 is 608993.

It is a Curzon number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 399806.

It is an unprimeable number.

399806 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 161 + ... + 908.

It is an arithmetic number, because the mean of its divisors is an integer number (43335).

2³⁹⁹⁸⁰⁶ is an apocalyptic number.

399806 is a deficient number, since it is larger than the sum of its proper divisors (293554).

399806 is a wasteful number, since it uses less digits than its factorization.

399806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1099.

The product of its (nonzero) digits is 11664, while the sum is 35.

The square root of 399806 is about 632.3021429665. The cubic root of 399806 is about 73.6687163447.

The spelling of 399806 in words is "three hundred ninety-nine thousand, eight hundred six".