78686612 has 6 divisors (see below), whose sum is σ = 137701578. Its totient is φ = 39343304.

The previous prime is 78686593. The next prime is 78686633. The reversal of 78686612 is 21668687.

It can be written as a sum of positive squares in only one way, i.e., 78605956 + 80656 = 8866^2 + 284^2 .

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 as a sum of consecutive naturals, namely, 9835823 + ... + 9835830.

It is an arithmetic number, because the mean of its divisors is an integer number (22950263).

Almost surely, 2^78686612 is an apocalyptic number.

It is an amenable number.

78686612 is a deficient number, since it is larger than the sum of its proper divisors (59014966).

78686612 is a wasteful number, since it uses less digits than its factorization.

78686612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19671657 (or 19671655 counting only the distinct ones).

The product of its digits is 193536, while the sum is 44.

The square root of 78686612 is about 8870.5474464657. The cubic root of 78686612 is about 428.5159077071.

The spelling of 78686612 in words is "seventy-eight million, six hundred eighty-six thousand, six hundred twelve".