681778368 has 84 divisors (see below), whose sum is σ = 2057079960. Its totient is φ = 215294976.

The previous prime is 681778367. The next prime is 681778369. The reversal of 681778368 is 863877186.

It is an interprime number because it is at equal distance from previous prime (681778367) and next prime (681778369).

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (681778367) 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 11 ways as a sum of consecutive naturals, for example, 20205 + ... + 42092.

Almost surely, 2^681778368 is an apocalyptic number.

It is an amenable number.

681778368 is an abundant number, since it is smaller than the sum of its proper divisors (1375301592).

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

681778368 is a wasteful number, since it uses less digits than its factorization.

681778368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62334 (or 62321 counting only the distinct ones).

The product of its digits is 2709504, while the sum is 54.

The square root of 681778368 is about 26110.8860056491. The cubic root of 681778368 is about 880.1318535212.

The spelling of 681778368 in words is "six hundred eighty-one million, seven hundred seventy-eight thousand, three hundred sixty-eight".