399947 has 4 divisors (see below), whose sum is σ = 417360. Its totient is φ = 382536.

The previous prime is 399941. The next prime is 399953. The reversal of 399947 is 749993.

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

It is an interprime number because it is at equal distance from previous prime (399941) and next prime (399953).

It is not a de Polignac number, because 399947 - 2⁸ = 399691 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399941) 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, 8672 + ... + 8717.

It is an arithmetic number, because the mean of its divisors is an integer number (104340).

2³⁹⁹⁹⁴⁷ is an apocalyptic number.

399947 is a deficient number, since it is larger than the sum of its proper divisors (17413).

399947 is a wasteful number, since it uses less digits than its factorization.

399947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17412.

The product of its digits is 61236, while the sum is 41.

The square root of 399947 is about 632.4136304666. The cubic root of 399947 is about 73.6773756012.

The spelling of 399947 in words is "three hundred ninety-nine thousand, nine hundred forty-seven".