681840528 has 40 divisors (see below), whose sum is σ = 1764122208. Its totient is φ = 226931712.

The previous prime is 681840503. The next prime is 681840529. The reversal of 681840528 is 825048186.

It is a self number, because there is not a number n which added to its sum of digits gives 681840528.

It is not an unprimeable number, because it can be changed into a prime (681840529) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 21751 + ... + 42857.

Almost surely, 2^681840528 is an apocalyptic number.

It is an amenable number.

681840528 is an abundant number, since it is smaller than the sum of its proper divisors (1082281680).

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

681840528 is a wasteful number, since it uses less digits than its factorization.

681840528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21791 (or 21785 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 42.

The square root of 681840528 is about 26112.0762866533. The cubic root of 681840528 is about 880.1586008905.

The spelling of 681840528 in words is "six hundred eighty-one million, eight hundred forty thousand, five hundred twenty-eight".