81825800 has 96 divisors (see below), whose sum is σ = 219241920. Its totient is φ = 27820800.

The previous prime is 81825787. The next prime is 81825803. The reversal of 81825800 is 852818.

It is not an unprimeable number, because it can be changed into a prime (81825803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 295262 + ... + 295538.

It is an arithmetic number, because the mean of its divisors is an integer number (2283770).

Almost surely, 2^81825800 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 81825800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109620960).

81825800 is an abundant number, since it is smaller than the sum of its proper divisors (137416120).

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

81825800 is a wasteful number, since it uses less digits than its factorization.

81825800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511 (or 502 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 32.

The square root of 81825800 is about 9045.7614383754. The cubic root of 81825800 is about 434.1402846634.

The spelling of 81825800 in words is "eighty-one million, eight hundred twenty-five thousand, eight hundred".