681889556 has 24 divisors (see below), whose sum is σ = 1310729280. Its totient is φ = 308956032.

The previous prime is 681889529. The next prime is 681889577. The reversal of 681889556 is 655988186.

It is a congruent number.

It is an unprimeable number.

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, 193301 + ... + 196796.

It is an arithmetic number, because the mean of its divisors is an integer number (54613720).

Almost surely, 2^681889556 is an apocalyptic number.

It is an amenable number.

681889556 is a deficient number, since it is larger than the sum of its proper divisors (628839724).

681889556 is a wasteful number, since it uses less digits than its factorization.

681889556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 390143 (or 390141 counting only the distinct ones).

The product of its digits is 4147200, while the sum is 56.

The square root of 681889556 is about 26113.0150691183. The cubic root of 681889556 is about 880.1796964301.

The spelling of 681889556 in words is "six hundred eighty-one million, eight hundred eighty-nine thousand, five hundred fifty-six".