81147993696000 has 6912 divisors, whose sum is σ = 401697214464000. Its totient is φ = 16094453760000.

The previous prime is 81147993695981. The next prime is 81147993696019. The reversal of 81147993696000 is 69639974118.

81147993696000 is a `hidden beast` number, since 8 + 1 + 14 + 7 + 9 + 9 + 3 + 6 + 9 + 600 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (81147993695981) and next prime (81147993696019).

It is a tau number, because it is divible by the number of its divisors (6912).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 767 ways as a sum of consecutive naturals, for example, 1111616351964 + ... + 1111616352036.

Almost surely, 2^{81147993696000} is an apocalyptic number.

81147993696000 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 81147993696000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (200848607232000).

81147993696000 is an abundant number, since it is smaller than the sum of its proper divisors (320549220768000).

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

81147993696000 is a wasteful number, since it uses less digits than its factorization.

81147993696000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187 (or 132 counting only the distinct ones).

The product of its (nonzero) digits is 17635968, while the sum is 63.

The spelling of 81147993696000 in words is "eighty-one trillion, one hundred forty-seven billion, nine hundred ninety-three million, six hundred ninety-six thousand".