381985 has 8 divisors (see below), whose sum is σ = 461736. Its totient is φ = 303360.

The previous prime is 381977. The next prime is 381989. The reversal of 381985 is 589183.

It can be written as a sum of positive squares in 4 ways, for example, as 12321 + 369664 = 111^2 + 608^2 .

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

It is not a de Polignac number, because 381985 - 2³ = 381977 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 381985.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381989) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1047 + ... + 1363.

It is an arithmetic number, because the mean of its divisors is an integer number (57717).

2³⁸¹⁹⁸⁵ is an apocalyptic number.

It is an amenable number.

381985 is a deficient number, since it is larger than the sum of its proper divisors (79751).

381985 is a wasteful number, since it uses less digits than its factorization.

381985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 563.

The product of its digits is 8640, while the sum is 34.

The square root of 381985 is about 618.0493507803. The cubic root of 381985 is about 72.5574653392.

Adding to 381985 its product of digits (8640), we get a 8-th power (390625 = 5⁸).

The spelling of 381985 in words is "three hundred eighty-one thousand, nine hundred eighty-five".