685679904 has 672 divisors, whose sum is σ = 2776394880. Its totient is φ = 161243136.

The previous prime is 685679903. The next prime is 685679909. The reversal of 685679904 is 409976586.

It is a tau number, because it is divible by the number of its divisors (672).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685679903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 36088407 + ... + 36088425.

It is an arithmetic number, because the mean of its divisors is an integer number (4131540).

Almost surely, 2^685679904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 685679904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1388197440).

685679904 is an abundant number, since it is smaller than the sum of its proper divisors (2090714976).

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

685679904 is a wasteful number, since it uses less digits than its factorization.

685679904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84 (or 61 counting only the distinct ones).

The product of its (nonzero) digits is 3265920, while the sum is 54.

The square root of 685679904 is about 26185.4903333888. The cubic root of 685679904 is about 881.8075381808.

The spelling of 685679904 in words is "six hundred eighty-five million, six hundred seventy-nine thousand, nine hundred four".