78939344393987 has 32 divisors (see below), whose sum is σ = 100542794655744. Its totient is φ = 60183913276800.

The previous prime is 78939344393971. The next prime is 78939344393993.

78939344393987 is nontrivially palindromic in base 10.

It is a cyclic number.

It is not a de Polignac number, because 78939344393987 - 2⁴ = 78939344393971 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 78939344393899 and 78939344393908.

It is not an unprimeable number, because it can be changed into a prime (78939344393927) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8419937 + ... + 15125277.

It is an arithmetic number, because the mean of its divisors is an integer number (3141962332992).

Almost surely, 2^{78939344393987} is an apocalyptic number.

78939344393987 is a gapful number since it is divisible by the number (77) formed by its first and last digit.

78939344393987 is a deficient number, since it is larger than the sum of its proper divisors (21603450261757).

78939344393987 is a wasteful number, since it uses less digits than its factorization.

78939344393987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6708659.

The product of its digits is 26665583616, while the sum is 86.

The spelling of 78939344393987 in words is "seventy-eight trillion, nine hundred thirty-nine billion, three hundred forty-four million, three hundred ninety-three thousand, nine hundred eighty-seven".