78856665887 has 2 divisors, whose sum is σ = 78856665888. Its totient is φ = 78856665886.

The previous prime is 78856665869. The next prime is 78856665931.

78856665887 is nontrivially palindromic in base 10.

It is a weak prime.

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 78856665887 - 2⁸ = 78856665631 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78856662887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39428332943 + 39428332944.

It is an arithmetic number, because the mean of its divisors is an integer number (39428332944).

Almost surely, 2^78856665887 is an apocalyptic number.

78856665887 is a deficient number, since it is larger than the sum of its proper divisors (1).

78856665887 is an equidigital number, since it uses as much as digits as its factorization.

78856665887 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1083801600, while the sum is 74.

The spelling of 78856665887 in words is "seventy-eight billion, eight hundred fifty-six million, six hundred sixty-five thousand, eight hundred eighty-seven".