78778 has 16 divisors (see below), whose sum is σ = 143424. Its totient is φ = 31680.

The previous prime is 78737. The next prime is 78779. The reversal of 78778 is 87787.

It is not an unprimeable number, because it can be changed into a prime (78779) 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, 73 + ... + 403.

It is an arithmetic number, because the mean of its divisors is an integer number (8964).

2⁷⁸⁷⁷⁸ is an apocalyptic number.

78778 is a deficient number, since it is larger than the sum of its proper divisors (64646).

78778 is a wasteful number, since it uses less digits than its factorization.

78778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 357.

The product of its digits is 21952, while the sum is 37.

The square root of 78778 is about 280.6741883394. The cubic root of 78778 is about 42.8681738801.

Subtracting 78778 from its reverse (87787), we obtain a palindrome (9009).

The spelling of 78778 in words is "seventy-eight thousand, seven hundred seventy-eight".