78516864 has 80 divisors (see below), whose sum is σ = 233695770. Its totient is φ = 26168832.

The previous prime is 78516859. The next prime is 78516869. The reversal of 78516864 is 46861587.

It is a happy number.

78516864 is a `hidden beast` number, since 78 + 516 + 8 + 64 = 666.

It is an interprime number because it is at equal distance from previous prime (78516859) and next prime (78516869).

It can be written as a sum of positive squares in only one way, i.e., 41062464 + 37454400 = 6408^2 + 6120^2 .

It is not an unprimeable number, because it can be changed into a prime (78516869) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 6582 + ... + 14154.

Almost surely, 2^78516864 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 78516864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (116847885).

78516864 is an abundant number, since it is smaller than the sum of its proper divisors (155178906).

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

78516864 is an equidigital number, since it uses as much as digits as its factorization.

78516864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7599 (or 7578 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The square root of 78516864 is about 8860.9742128053. The cubic root of 78516864 is about 428.2075448419.

The spelling of 78516864 in words is "seventy-eight million, five hundred sixteen thousand, eight hundred sixty-four".