686840816 has 10 divisors (see below), whose sum is σ = 1330754112. Its totient is φ = 343420400.

The previous prime is 686840813. The next prime is 686840821. The reversal of 686840816 is 618048686.

686840816 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686840813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21463760 + ... + 21463791.

Almost surely, 2^686840816 is an apocalyptic number.

It is an amenable number.

686840816 is a deficient number, since it is larger than the sum of its proper divisors (643913296).

686840816 is a wasteful number, since it uses less digits than its factorization.

686840816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42927559 (or 42927553 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 47.

The square root of 686840816 is about 26207.6480440348. The cubic root of 686840816 is about 882.3049149466.

The spelling of 686840816 in words is "six hundred eighty-six million, eight hundred forty thousand, eight hundred sixteen".