6686894986865 has 8 divisors (see below), whose sum is σ = 8024924165568. Its totient is φ = 5349082535280.

The previous prime is 6686894986823. The next prime is 6686894986897. The reversal of 6686894986865 is 5686894986866.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-6686894986865 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54113891 + ... + 54237320.

It is an arithmetic number, because the mean of its divisors is an integer number (1003115520696).

Almost surely, 2^{6686894986865} is an apocalyptic number.

It is an amenable number.

6686894986865 is a deficient number, since it is larger than the sum of its proper divisors (1338029178703).

6686894986865 is a wasteful number, since it uses less digits than its factorization.

6686894986865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108363559.

The product of its digits is 51597803520, while the sum is 89.

Subtracting from 6686894986865 its reverse (5686894986866), we obtain a palindrome (999999999999).

The spelling of 6686894986865 in words is "six trillion, six hundred eighty-six billion, eight hundred ninety-four million, nine hundred eighty-six thousand, eight hundred sixty-five".