681657766336 has 28 divisors (see below), whose sum is σ = 1423857507880. Its totient is φ = 322890520320.

The previous prime is 681657766303. The next prime is 681657766379. The reversal of 681657766336 is 633667756186.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (64).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 280285695 + ... + 280288126.

Almost surely, 2^681657766336 is an apocalyptic number.

It is an amenable number.

681657766336 is an abundant number, since it is smaller than the sum of its proper divisors (742199741544).

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

681657766336 is a wasteful number, since it uses less digits than its factorization.

681657766336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560573852 (or 560573842 counting only the distinct ones).

The product of its digits is 137168640, while the sum is 64.

The spelling of 681657766336 in words is "six hundred eighty-one billion, six hundred fifty-seven million, seven hundred sixty-six thousand, three hundred thirty-six".