681565500 has 432 divisors, whose sum is σ = 2738238048. Its totient is φ = 141120000.

The previous prime is 681565483. The next prime is 681565501. The reversal of 681565500 is 5565186.

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 (681565501) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 2425360 + ... + 2425640.

It is an arithmetic number, because the mean of its divisors is an integer number (6338514).

Almost surely, 2^681565500 is an apocalyptic number.

681565500 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 681565500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1369119024).

681565500 is an abundant number, since it is smaller than the sum of its proper divisors (2056672548).

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

681565500 is a wasteful number, since it uses less digits than its factorization.

681565500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331 (or 309 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 36.

The square root of 681565500 is about 26106.8094565383. The cubic root of 681565500 is about 880.0402443716.

The spelling of 681565500 in words is "six hundred eighty-one million, five hundred sixty-five thousand, five hundred".