78685258687 has 4 divisors (see below), whose sum is σ = 89926009936. Its totient is φ = 67444507440.

The previous prime is 78685258637. The next prime is 78685258711.

78685258687 is nontrivially palindromic in base 10.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78685258687 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78685258637) 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, 5620375614 + ... + 5620375627.

It is an arithmetic number, because the mean of its divisors is an integer number (22481502484).

Almost surely, 2^78685258687 is an apocalyptic number.

78685258687 is a deficient number, since it is larger than the sum of its proper divisors (11240751249).

78685258687 is a wasteful number, since it uses less digits than its factorization.

78685258687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11240751248.

The product of its digits is 361267200, while the sum is 70.

The spelling of 78685258687 in words is "seventy-eight billion, six hundred eighty-five million, two hundred fifty-eight thousand, six hundred eighty-seven".