238640 has 40 divisors (see below), whose sum is σ = 587760. Its totient is φ = 89856.

The previous prime is 238639. The next prime is 238649. The reversal of 238640 is 46832.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (238649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1442 + ... + 1598.

It is an arithmetic number, because the mean of its divisors is an integer number (14694).

2²³⁸⁶⁴⁰ is an apocalyptic number.

238640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 238640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (293880).

238640 is an abundant number, since it is smaller than the sum of its proper divisors (349120).

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

238640 is a wasteful number, since it uses less digits than its factorization.

238640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189 (or 183 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 238640 is about 488.5079323819. The cubic root of 238640 is about 62.0270433533.

It can be divided in two parts, 238 and 640, that added together give a palindrome (878).

The spelling of 238640 in words is "two hundred thirty-eight thousand, six hundred forty".