684040686 has 24 divisors (see below), whose sum is σ = 1591442280. Its totient is φ = 195440112.

The previous prime is 684040649. The next prime is 684040711. The reversal of 684040686 is 686040486.

684040686 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1163041 + ... + 1163628.

It is an arithmetic number, because the mean of its divisors is an integer number (66310095).

Almost surely, 2^684040686 is an apocalyptic number.

684040686 is an abundant number, since it is smaller than the sum of its proper divisors (907401594).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

684040686 is a wasteful number, since it uses less digits than its factorization.

684040686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2326688 (or 2326681 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 42.

The square root of 684040686 is about 26154.1714837232. The cubic root of 684040686 is about 881.1042808805.

The spelling of 684040686 in words is "six hundred eighty-four million, forty thousand, six hundred eighty-six".