684728678 has 8 divisors (see below), whose sum is σ = 1028653560. Its totient is φ = 341844160.

The previous prime is 684728647. The next prime is 684728683. The reversal of 684728678 is 876827486.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 258443 + ... + 261078.

It is an arithmetic number, because the mean of its divisors is an integer number (128581695).

Almost surely, 2^684728678 is an apocalyptic number.

684728678 is a deficient number, since it is larger than the sum of its proper divisors (343924882).

684728678 is a wasteful number, since it uses less digits than its factorization.

684728678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 520182.

The product of its digits is 7225344, while the sum is 56.

The square root of 684728678 is about 26167.3208028640. The cubic root of 684728678 is about 881.3995798741.

The spelling of 684728678 in words is "six hundred eighty-four million, seven hundred twenty-eight thousand, six hundred seventy-eight".