78678138 has 32 divisors (see below), whose sum is σ = 196185600. Its totient is φ = 20435760.

The previous prime is 78678133. The next prime is 78678143. The reversal of 78678138 is 83187687.

It is an interprime number because it is at equal distance from previous prime (78678133) and next prime (78678143).

It is not an unprimeable number, because it can be changed into a prime (78678133) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 84688 + ... + 85611.

It is an arithmetic number, because the mean of its divisors is an integer number (6130800).

Almost surely, 2^78678138 is an apocalyptic number.

78678138 is an abundant number, since it is smaller than the sum of its proper divisors (117507462).

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

78678138 is a wasteful number, since it uses less digits than its factorization.

78678138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170322.

The product of its digits is 451584, while the sum is 48.

The square root of 78678138 is about 8870.0697855203. The cubic root of 78678138 is about 428.5005244288.

The spelling of 78678138 in words is "seventy-eight million, six hundred seventy-eight thousand, one hundred thirty-eight".