681809700 has 288 divisors, whose sum is σ = 2421844992. Its totient is φ = 145728000.

The previous prime is 681809669. The next prime is 681809719. The reversal of 681809700 is 7908186.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

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 95 ways as a sum of consecutive naturals, for example, 986355 + ... + 987045.

It is an arithmetic number, because the mean of its divisors is an integer number (8409184).

Almost surely, 2^681809700 is an apocalyptic number.

681809700 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 681809700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1210922496).

681809700 is an abundant number, since it is smaller than the sum of its proper divisors (1740035292).

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

681809700 is a wasteful number, since it uses less digits than its factorization.

681809700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 755 (or 748 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 39.

The square root of 681809700 is about 26111.4859783966. The cubic root of 681809700 is about 880.1453358443.

The spelling of 681809700 in words is "six hundred eighty-one million, eight hundred nine thousand, seven hundred".