978891678 has 12 divisors (see below), whose sum is σ = 2120932008. Its totient is φ = 326297220.

The previous prime is 978891673. The next prime is 978891691. The reversal of 978891678 is 876198879.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (978891673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 27191418 + ... + 27191453.

It is an arithmetic number, because the mean of its divisors is an integer number (176744334).

Almost surely, 2^978891678 is an apocalyptic number.

978891678 is an abundant number, since it is smaller than the sum of its proper divisors (1142040330).

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

978891678 is a wasteful number, since it uses less digits than its factorization.

978891678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54382879 (or 54382876 counting only the distinct ones).

The product of its digits is 12192768, while the sum is 63.

The square root of 978891678 is about 31287.2446533727. The cubic root of 978891678 is about 992.9137970033.

The spelling of 978891678 in words is "nine hundred seventy-eight million, eight hundred ninety-one thousand, six hundred seventy-eight".