4381 has 4 divisors (see below), whose sum is σ = 4732. Its totient is φ = 4032.

The previous prime is 4373. The next prime is 4391. The reversal of 4381 is 1834.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 900 + 3481 = 30^2 + 59^2 .

It is a cyclic number.

It is not a de Polignac number, because 4381 - 2³ = 4373 is a prime.

It is a super-2 number, since 2×4381² = 38386322, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4391) 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, 156 + ... + 181.

It is an arithmetic number, because the mean of its divisors is an integer number (1183).

2⁴³⁸¹ is an apocalyptic number.

It is an amenable number.

4381 is a deficient number, since it is larger than the sum of its proper divisors (351).

4381 is a wasteful number, since it uses less digits than its factorization.

4381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 350.

The product of its digits is 96, while the sum is 16.

The square root of 4381 is about 66.1891229735. The cubic root of 4381 is about 16.3628048586.

The spelling of 4381 in words is "four thousand, three hundred eighty-one".