78478 has 4 divisors (see below), whose sum is σ = 117720. Its totient is φ = 39238.

The previous prime is 78467. The next prime is 78479. The reversal of 78478 is 87487.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87487 = 89 ⋅983.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78479) by changing a digit.

78478 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 as a sum of consecutive naturals, namely, 19618 + ... + 19621.

It is an arithmetic number, because the mean of its divisors is an integer number (29430).

2⁷⁸⁴⁷⁸ is an apocalyptic number.

78478 is a deficient number, since it is larger than the sum of its proper divisors (39242).

78478 is a wasteful number, since it uses less digits than its factorization.

78478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39241.

The product of its digits is 12544, while the sum is 34.

The square root of 78478 is about 280.1392510877. The cubic root of 78478 is about 42.8136882296.

Subtracting 78478 from its reverse (87487), we obtain a palindrome (9009).

The spelling of 78478 in words is "seventy-eight thousand, four hundred seventy-eight".