78689755798687 has 4 divisors (see below), whose sum is σ = 85843369962216. Its totient is φ = 71536141635160.

The previous prime is 78689755798613. The next prime is 78689755798729.

It is a happy number.

78689755798687 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-78689755798687 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78689755798592 and 78689755798601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78689755790687) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3576807081748 + ... + 3576807081769.

It is an arithmetic number, because the mean of its divisors is an integer number (21460842490554).

Almost surely, 2^{78689755798687} is an apocalyptic number.

78689755798687 is a deficient number, since it is larger than the sum of its proper divisors (7153614163529).

78689755798687 is a wasteful number, since it uses less digits than its factorization.

78689755798687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7153614163528.

The product of its digits is 716934758400, while the sum is 100.

The spelling of 78689755798687 in words is "seventy-eight trillion, six hundred eighty-nine billion, seven hundred fifty-five million, seven hundred ninety-eight thousand, six hundred eighty-seven".