399287 has 4 divisors (see below), whose sum is σ = 456336. Its totient is φ = 342240.

The previous prime is 399283. The next prime is 399353. The reversal of 399287 is 782993.

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 399287 - 2² = 399283 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 399287.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399281) 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, 28514 + ... + 28527.

It is an arithmetic number, because the mean of its divisors is an integer number (114084).

2³⁹⁹²⁸⁷ is an apocalyptic number.

399287 is a deficient number, since it is larger than the sum of its proper divisors (57049).

399287 is an equidigital number, since it uses as much as digits as its factorization.

399287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57048.

The product of its digits is 27216, while the sum is 38.

The square root of 399287 is about 631.8916046285. The cubic root of 399287 is about 73.6368253609.

It can be divided in two parts, 399 and 287, that added together give a palindrome (686).

The spelling of 399287 in words is "three hundred ninety-nine thousand, two hundred eighty-seven".