681563427768 has 48 divisors (see below), whose sum is σ = 1845939087720. Its totient is φ = 227183115456.

The previous prime is 681563427737. The next prime is 681563427773. The reversal of 681563427768 is 867724365186.

681563427768 is a `hidden beast` number, since 6 + 8 + 1 + 563 + 4 + 2 + 7 + 7 + 68 = 666.

It is a super-3 number, since 3×681563427768³ (a number of 36 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

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 11 ways as a sum of consecutive naturals, for example, 6280255 + ... + 6387857.

Almost surely, 2^681563427768 is an apocalyptic number.

It is an amenable number.

681563427768 is an abundant number, since it is smaller than the sum of its proper divisors (1164375659952).

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

681563427768 is a wasteful number, since it uses less digits than its factorization.

681563427768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195588 (or 195581 counting only the distinct ones).

The product of its digits is 81285120, while the sum is 63.

The spelling of 681563427768 in words is "six hundred eighty-one billion, five hundred sixty-three million, four hundred twenty-seven thousand, seven hundred sixty-eight".