399867 has 8 divisors (see below), whose sum is σ = 574224. Its totient is φ = 246048.

The previous prime is 399853. The next prime is 399871. The reversal of 399867 is 768993.

It is a happy number.

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

It is not a de Polignac number, because 399867 - 2⁴ = 399851 is a prime.

399867 is a lucky number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 399867.

It is not an unprimeable number, because it can be changed into a prime (399887) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5088 + ... + 5165.

It is an arithmetic number, because the mean of its divisors is an integer number (71778).

2³⁹⁹⁸⁶⁷ is an apocalyptic number.

399867 is a deficient number, since it is larger than the sum of its proper divisors (174357).

399867 is a wasteful number, since it uses less digits than its factorization.

399867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10269.

The product of its digits is 81648, while the sum is 42.

The square root of 399867 is about 632.3503775598. The cubic root of 399867 is about 73.6724627977.

It can be divided in two parts, 39986 and 7, that added together give a palindrome (39993).

The spelling of 399867 in words is "three hundred ninety-nine thousand, eight hundred sixty-seven".