81942336000 has 480 divisors, whose sum is σ = 337320517248. Its totient is φ = 18728755200.

The previous prime is 81942335879. The next prime is 81942336019. The reversal of 81942336000 is 63324918.

81942336000 is a `hidden beast` number, since 8 + 1 + 9 + 42 + 3 + 3 + 600 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4021839 + ... + 4042161.

Almost surely, 2^81942336000 is an apocalyptic number.

81942336000 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 81942336000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (168660258624).

81942336000 is an abundant number, since it is smaller than the sum of its proper divisors (255378181248).

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

81942336000 is a wasteful number, since it uses less digits than its factorization.

81942336000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20369 (or 20340 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The spelling of 81942336000 in words is "eighty-one billion, nine hundred forty-two million, three hundred thirty-six thousand".