78686868 has 24 divisors (see below), whose sum is σ = 197726368. Its totient is φ = 24211296.

The previous prime is 78686857. The next prime is 78686873. The reversal of 78686868 is 86868687.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252046 + ... + 252357.

Almost surely, 2^78686868 is an apocalyptic number.

78686868 is a gapful number since it is divisible by the number (78) formed by its first and last digit.

It is an amenable number.

78686868 is an abundant number, since it is smaller than the sum of its proper divisors (119039500).

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

78686868 is a wasteful number, since it uses less digits than its factorization.

78686868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504423 (or 504421 counting only the distinct ones).

The product of its digits is 6193152, while the sum is 57.

The square root of 78686868 is about 8870.5618762286. The cubic root of 78686868 is about 428.5163724196.

The spelling of 78686868 in words is "seventy-eight million, six hundred eighty-six thousand, eight hundred sixty-eight".