681256800 has 324 divisors, whose sum is σ = 2795938236. Its totient is φ = 155635200.

The previous prime is 681256789. The next prime is 681256801. The reversal of 681256800 is 8652186.

It is a happy number.

It is a super-2 number, since 2×681256800² = 928221655092480000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681256801) 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 53 ways as a sum of consecutive naturals, for example, 351835 + ... + 353765.

It is an arithmetic number, because the mean of its divisors is an integer number (8629439).

Almost surely, 2^681256800 is an apocalyptic number.

681256800 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 681256800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1397969118).

681256800 is an abundant number, since it is smaller than the sum of its proper divisors (2114681436).

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

681256800 is a wasteful number, since it uses less digits than its factorization.

681256800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1971 (or 1948 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 681256800 is about 26100.8965363261. The cubic root of 681256800 is about 879.9073593938.

The spelling of 681256800 in words is "six hundred eighty-one million, two hundred fifty-six thousand, eight hundred".