81394796381184 has 1408 divisors, whose sum is σ = 286801010496000. Its totient is φ = 22479938519040.

The previous prime is 81394796381123. The next prime is 81394796381191. The reversal of 81394796381184 is 48118369749318.

81394796381184 is a `hidden beast` number, since 8 + 1 + 3 + 9 + 479 + 6 + 38 + 118 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (1408).

It is a super-3 number, since 3×81394796381184³ (a number of 43 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 137259352792 + ... + 137259353384.

It is an arithmetic number, because the mean of its divisors is an integer number (203693899500).

Almost surely, 2^{81394796381184} 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 81394796381184, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143400505248000).

81394796381184 is an abundant number, since it is smaller than the sum of its proper divisors (205406214114816).

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

81394796381184 is a wasteful number, since it uses less digits than its factorization.

81394796381184 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1028 (or 1004 counting only the distinct ones).

The product of its digits is 250822656, while the sum is 72.

The spelling of 81394796381184 in words is "eighty-one trillion, three hundred ninety-four billion, seven hundred ninety-six million, three hundred eighty-one thousand, one hundred eighty-four".