78438 has 16 divisors (see below), whose sum is σ = 166320. Its totient is φ = 24576.

The previous prime is 78437. The next prime is 78439. The reversal of 78438 is 83487.

It is an interprime number because it is at equal distance from previous prime (78437) and next prime (78439).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78437) 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, 283 + ... + 486.

It is an arithmetic number, because the mean of its divisors is an integer number (10395).

2⁷⁸⁴³⁸ is an apocalyptic number.

78438 is an abundant number, since it is smaller than the sum of its proper divisors (87882).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83160).

78438 is a wasteful number, since it uses less digits than its factorization.

78438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 791.

The product of its digits is 5376, while the sum is 30.

The square root of 78438 is about 280.0678489224. The cubic root of 78438 is about 42.8064129908.

It can be divided in two parts, 784 and 38, that multiplied together give a palindrome (29792).

The spelling of 78438 in words is "seventy-eight thousand, four hundred thirty-eight".