38440 has 24 divisors (see below), whose sum is σ = 89370. Its totient is φ = 14880.

The previous prime is 38431. The next prime is 38447. The reversal of 38440 is 4483.

It can be written as a sum of positive squares in only one way, i.e., 34596 + 3844 = 186^2 + 62^2 .

It is a Smith number, since the sum of its digits (19) coincides with the sum of the digits of its prime factors.

It is a zygodrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (38447) by changing a digit.

38440 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1225 + ... + 1255.

2³⁸⁴⁴⁰ 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 38440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44685).

38440 is an abundant number, since it is smaller than the sum of its proper divisors (50930).

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

38440 is a wasteful number, since it uses less digits than its factorization.

38440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73 (or 38 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 38440 is about 196.0612149304. The cubic root of 38440 is about 33.7490168895.

It can be divided in two parts, 384 and 40, that added together give a palindrome (424).

The spelling of 38440 in words is "thirty-eight thousand, four hundred forty".