78685255867 has 2 divisors, whose sum is σ = 78685255868. Its totient is φ = 78685255866.

The previous prime is 78685255849. The next prime is 78685255877. The reversal of 78685255867 is 76855258687.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78685255867 is a prime.

It is not a weakly prime, because it can be changed into another prime (78685255877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39342627933 + 39342627934.

It is an arithmetic number, because the mean of its divisors is an integer number (39342627934).

Almost surely, 2^78685255867 is an apocalyptic number.

78685255867 is a deficient number, since it is larger than the sum of its proper divisors (1).

78685255867 is an equidigital number, since it uses as much as digits as its factorization.

78685255867 is an evil number, because the sum of its binary digits is even.

The product of its digits is 225792000, while the sum is 67.

The spelling of 78685255867 in words is "seventy-eight billion, six hundred eighty-five million, two hundred fifty-five thousand, eight hundred sixty-seven".