399705 has 8 divisors (see below), whose sum is σ = 639552. Its totient is φ = 213168.

The previous prime is 399691. The next prime is 399719. The reversal of 399705 is 507993.

It is an interprime number because it is at equal distance from previous prime (399691) and next prime (399719).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 399705 - 2⁴ = 399689 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13309 + ... + 13338.

It is an arithmetic number, because the mean of its divisors is an integer number (79944).

2³⁹⁹⁷⁰⁵ is an apocalyptic number.

It is an amenable number.

399705 is a deficient number, since it is larger than the sum of its proper divisors (239847).

399705 is a wasteful number, since it uses less digits than its factorization.

399705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26655.

The product of its (nonzero) digits is 8505, while the sum is 33.

The square root of 399705 is about 632.2222710408. Note that the first 4 decimals coincide. The cubic root of 399705 is about 73.6625123633.

The spelling of 399705 in words is "three hundred ninety-nine thousand, seven hundred five".