384840 has 48 divisors (see below), whose sum is σ = 1251900. Its totient is φ = 102528.

The previous prime is 384827. The next prime is 384841. The reversal of 384840 is 48483.

384840 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 381924 + 2916 = 618^2 + 54^2 .

It is not an unprimeable number, because it can be changed into a prime (384841) by changing a digit.

384840 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 11 ways as a sum of consecutive naturals, for example, 175 + ... + 894.

2³⁸⁴⁸⁴⁰ is an apocalyptic number.

384840 is a gapful number since it is divisible by the number (30) 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 384840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (625950).

384840 is an abundant number, since it is smaller than the sum of its proper divisors (867060).

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

384840 is a wasteful number, since it uses less digits than its factorization.

384840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1086 (or 1079 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 384840 is about 620.3547372270. The cubic root of 384840 is about 72.7377844654.

The spelling of 384840 in words is "three hundred eighty-four thousand, eight hundred forty".