686212216823 has 16 divisors (see below), whose sum is σ = 831634594560. Its totient is φ = 552742866816.

The previous prime is 686212216813. The next prime is 686212216829. The reversal of 686212216823 is 328612212686.

It is a happy number.

It is not a de Polignac number, because 686212216823 - 2⁸ = 686212216567 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686212216829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4296761 + ... + 4453602.

It is an arithmetic number, because the mean of its divisors is an integer number (51977162160).

Almost surely, 2^686212216823 is an apocalyptic number.

686212216823 is a deficient number, since it is larger than the sum of its proper divisors (145422377737).

686212216823 is a wasteful number, since it uses less digits than its factorization.

686212216823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8751046.

The product of its digits is 663552, while the sum is 47.

The spelling of 686212216823 in words is "six hundred eighty-six billion, two hundred twelve million, two hundred sixteen thousand, eight hundred twenty-three".