384640 has 32 divisors (see below), whose sum is σ = 921060. Its totient is φ = 153600.

The previous prime is 384623. The next prime is 384641. The reversal of 384640 is 46483.

It can be written as a sum of positive squares in 2 ways, for example, as 379456 + 5184 = 616^2 + 72^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (384641) 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, 340 + ... + 940.

2³⁸⁴⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 384640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (460530).

384640 is an abundant number, since it is smaller than the sum of its proper divisors (536420).

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

384640 is an equidigital number, since it uses as much as digits as its factorization.

384640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 620 (or 608 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 384640 is about 620.1935181861. The cubic root of 384640 is about 72.7251817581.

It can be divided in two parts, 384 and 640, that added together give a 10-th power (1024 = 2¹⁰).

The spelling of 384640 in words is "three hundred eighty-four thousand, six hundred forty".