684347640 has 32 divisors (see below), whose sum is σ = 2053043280. Its totient is φ = 182492672.

The previous prime is 684347627. The next prime is 684347647. The reversal of 684347640 is 46743486.

It is a junction number, because it is equal to n+sod(n) for n = 684347592 and 684347601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684347647) 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 7 ways as a sum of consecutive naturals, for example, 2851329 + ... + 2851568.

Almost surely, 2^684347640 is an apocalyptic number.

684347640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

684347640 is an abundant number, since it is smaller than the sum of its proper divisors (1368695640).

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

684347640 is a wasteful number, since it uses less digits than its factorization.

684347640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5702911 (or 5702907 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 42.

The square root of 684347640 is about 26160.0389907966. The cubic root of 684347640 is about 881.2360557122.

The spelling of 684347640 in words is "six hundred eighty-four million, three hundred forty-seven thousand, six hundred forty".