78631108779 has 4 divisors (see below), whose sum is σ = 104841478376. Its totient is φ = 52420739184.

The previous prime is 78631108697. The next prime is 78631108807. The reversal of 78631108779 is 97780113687.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 78631108779 - 2⁷ = 78631108651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78631108079) 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 3 ways as a sum of consecutive naturals, for example, 13105184794 + ... + 13105184799.

It is an arithmetic number, because the mean of its divisors is an integer number (26210369594).

Almost surely, 2^78631108779 is an apocalyptic number.

78631108779 is a deficient number, since it is larger than the sum of its proper divisors (26210369597).

78631108779 is a wasteful number, since it uses less digits than its factorization.

78631108779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26210369596.

The product of its (nonzero) digits is 3556224, while the sum is 57.

The spelling of 78631108779 in words is "seventy-eight billion, six hundred thirty-one million, one hundred eight thousand, seven hundred seventy-nine".