81385874824800 has 2304 divisors, whose sum is σ = 347079225507840. Its totient is φ = 16106397696000.

The previous prime is 81385874824747. The next prime is 81385874824811. The reversal of 81385874824800 is 842847858318.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 29160111405 + ... + 29160114195.

It is an arithmetic number, because the mean of its divisors is an integer number (150642024960).

Almost surely, 2^{81385874824800} is an apocalyptic number.

81385874824800 is a gapful number since it is divisible by the number (80) 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 81385874824800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173539612753920).

81385874824800 is an abundant number, since it is smaller than the sum of its proper divisors (265693350683040).

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

81385874824800 is a wasteful number, since it uses less digits than its factorization.

81385874824800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2997 (or 2984 counting only the distinct ones).

The product of its (nonzero) digits is 110100480, while the sum is 66.

The spelling of 81385874824800 in words is "eighty-one trillion, three hundred eighty-five billion, eight hundred seventy-four million, eight hundred twenty-four thousand, eight hundred".