399895 has 4 divisors (see below), whose sum is σ = 479880. Its totient is φ = 319912.

The previous prime is 399887. The next prime is 399899. The reversal of 399895 is 598993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 598993 = 37 ⋅16189.

It is a cyclic number.

It is not a de Polignac number, because 399895 - 2³ = 399887 is a prime.

It is a super-2 number, since 2×399895² = 319832022050, which contains 22 as substring.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399899) 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, 39985 + ... + 39994.

It is an arithmetic number, because the mean of its divisors is an integer number (119970).

2³⁹⁹⁸⁹⁵ is an apocalyptic number.

399895 is a deficient number, since it is larger than the sum of its proper divisors (79985).

399895 is an equidigital number, since it uses as much as digits as its factorization.

399895 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79984.

The product of its digits is 87480, while the sum is 43.

The square root of 399895 is about 632.3725167969. The cubic root of 399895 is about 73.6741823535.

The spelling of 399895 in words is "three hundred ninety-nine thousand, eight hundred ninety-five".