681363648 has 168 divisors, whose sum is σ = 2243035392. Its totient is φ = 193715712.

The previous prime is 681363637. The next prime is 681363673. The reversal of 681363648 is 846363186.

681363648 is a `hidden beast` number, since 6 + 8 + 1 + 3 + 636 + 4 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (168).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 1398861 + ... + 1399347.

Almost surely, 2^681363648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 681363648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1121517696).

681363648 is an abundant number, since it is smaller than the sum of its proper divisors (1561671744).

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

681363648 is a wasteful number, since it uses less digits than its factorization.

681363648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 859 (or 846 counting only the distinct ones).

The product of its digits is 497664, while the sum is 45.

The square root of 681363648 is about 26102.9432823197. The cubic root of 681363648 is about 879.9533584095.

The spelling of 681363648 in words is "six hundred eighty-one million, three hundred sixty-three thousand, six hundred forty-eight".