385840 has 80 divisors (see below), whose sum is σ = 1124928. Its totient is φ = 119808.

The previous prime is 385837. The next prime is 385843. The reversal of 385840 is 48583.

It is an interprime number because it is at equal distance from previous prime (385837) and next prime (385843).

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 385799 and 385808.

It is not an unprimeable number, because it can be changed into a prime (385843) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7254 + ... + 7306.

2³⁸⁵⁸⁴⁰ 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 385840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (562464).

385840 is an abundant number, since it is smaller than the sum of its proper divisors (739088).

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

385840 is a wasteful number, since it uses less digits than its factorization.

385840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86 (or 80 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 385840 is about 621.1602047781. The cubic root of 385840 is about 72.8007325934.

It can be divided in two parts, 385 and 840, that added together give a triangular number (1225 = T₄₉).

The spelling of 385840 in words is "three hundred eighty-five thousand, eight hundred forty".