81150056064 has 768 divisors, whose sum is σ = 311946485760. Its totient is φ = 20379340800.

The previous prime is 81150056063. The next prime is 81150056069. The reversal of 81150056064 is 46065005118.

81150056064 is a `hidden beast` number, since 81 + 15 + 0 + 0 + 560 + 6 + 4 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (81150056063) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 74244702 + ... + 74245794.

It is an arithmetic number, because the mean of its divisors is an integer number (406180320).

Almost surely, 2^81150056064 is an apocalyptic number.

81150056064 is a gapful number since it is divisible by the number (84) 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 81150056064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (155973242880).

81150056064 is an abundant number, since it is smaller than the sum of its proper divisors (230796429696).

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

81150056064 is a wasteful number, since it uses less digits than its factorization.

81150056064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1171 (or 1147 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The spelling of 81150056064 in words is "eighty-one billion, one hundred fifty million, fifty-six thousand, sixty-four".