399305 has 4 divisors (see below), whose sum is σ = 479172. Its totient is φ = 319440.

The previous prime is 399283. The next prime is 399353. The reversal of 399305 is 503993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 503993 = 7 ⋅71999.

It can be written as a sum of positive squares in 2 ways, for example, as 283024 + 116281 = 532^2 + 341^2 .

It is not a de Polignac number, because 399305 - 2⁶ = 399241 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39926 + ... + 39935.

It is an arithmetic number, because the mean of its divisors is an integer number (119793).

2³⁹⁹³⁰⁵ is an apocalyptic number.

It is an amenable number.

399305 is a deficient number, since it is larger than the sum of its proper divisors (79867).

399305 is an equidigital number, since it uses as much as digits as its factorization.

399305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79866.

The product of its (nonzero) digits is 3645, while the sum is 29.

The square root of 399305 is about 631.9058474172. The cubic root of 399305 is about 73.6379318691.

The spelling of 399305 in words is "three hundred ninety-nine thousand, three hundred five".