399278 has 8 divisors (see below), whose sum is σ = 653400. Its totient is φ = 181480.

The previous prime is 399277. The next prime is 399281. The reversal of 399278 is 872993.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9053 + ... + 9096.

It is an arithmetic number, because the mean of its divisors is an integer number (81675).

2³⁹⁹²⁷⁸ is an apocalyptic number.

399278 is a deficient number, since it is larger than the sum of its proper divisors (254122).

399278 is a wasteful number, since it uses less digits than its factorization.

399278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18162.

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

The square root of 399278 is about 631.8844831138. The cubic root of 399278 is about 73.6362720944.

The spelling of 399278 in words is "three hundred ninety-nine thousand, two hundred seventy-eight".