399407 has 4 divisors (see below), whose sum is σ = 401016. Its totient is φ = 397800.

The previous prime is 399403. The next prime is 399409. The reversal of 399407 is 704993.

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 399407 - 2² = 399403 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399401) 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, 344 + ... + 957.

It is an arithmetic number, because the mean of its divisors is an integer number (100254).

2³⁹⁹⁴⁰⁷ is an apocalyptic number.

399407 is a deficient number, since it is larger than the sum of its proper divisors (1609).

399407 is a wasteful number, since it uses less digits than its factorization.

399407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1608.

The product of its (nonzero) digits is 6804, while the sum is 32.

The square root of 399407 is about 631.9865504898. The cubic root of 399407 is about 73.6442014538.

The spelling of 399407 in words is "three hundred ninety-nine thousand, four hundred seven".