78644688 has 20 divisors (see below), whose sum is σ = 203165568. Its totient is φ = 26214880.

The previous prime is 78644663. The next prime is 78644711. The reversal of 78644688 is 88644687.

It is a self number, because there is not a number n which added to its sum of digits gives 78644688.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 819168 + ... + 819263.

Almost surely, 2^78644688 is an apocalyptic number.

It is an amenable number.

78644688 is an abundant number, since it is smaller than the sum of its proper divisors (124520880).

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

78644688 is a wasteful number, since it uses less digits than its factorization.

78644688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1638442 (or 1638436 counting only the distinct ones).

The product of its digits is 2064384, while the sum is 51.

The square root of 78644688 is about 8868.1840305668. The cubic root of 78644688 is about 428.4397901738.

Subtracting 78644688 from its reverse (88644687), we obtain a palindrome (9999999).

The spelling of 78644688 in words is "seventy-eight million, six hundred forty-four thousand, six hundred eighty-eight".