399872 has 40 divisors (see below), whose sum is σ = 883872. Its totient is φ = 179200.

The previous prime is 399871. The next prime is 399887. The reversal of 399872 is 278993.

Its product of digits (27216) is a multiple of the sum of its prime divisors (84).

It is not an unprimeable number, because it can be changed into a prime (399871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5597 + ... + 5667.

2³⁹⁹⁸⁷² is an apocalyptic number.

399872 is a gapful number since it is divisible by the number (32) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 399872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (441936).

399872 is an abundant number, since it is smaller than the sum of its proper divisors (484000).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

399872 is an equidigital number, since it uses as much as digits as its factorization.

399872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100 (or 84 counting only the distinct ones).

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

The square root of 399872 is about 632.3543310518. The cubic root of 399872 is about 73.6727698671.

The spelling of 399872 in words is "three hundred ninety-nine thousand, eight hundred seventy-two".