681440000 has 90 divisors (see below), whose sum is σ = 1700127660. Its totient is φ = 272512000.

The previous prime is 681439991. The next prime is 681440003. The reversal of 681440000 is 44186.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (681440003) by changing a digit.

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 9 ways as a sum of consecutive naturals, for example, 157871 + ... + 162129.

Almost surely, 2^681440000 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 681440000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (850063830).

681440000 is an abundant number, since it is smaller than the sum of its proper divisors (1018687660).

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

681440000 is an frugal number, since it uses more digits than its factorization.

681440000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4295 (or 4266 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 681440000 is about 26104.4057584156. The cubic root of 681440000 is about 879.9862256797.

Adding to 681440000 its reverse (44186), we get a palindrome (681484186).

The spelling of 681440000 in words is "six hundred eighty-one million, four hundred forty thousand".