81668440271088 has 240 divisors, whose sum is σ = 258728202120960. Its totient is φ = 23832018201600.

The previous prime is 81668440271069. The next prime is 81668440271111. The reversal of 81668440271088 is 88017204486618.

81668440271088 is a `hidden beast` number, since 8 + 1 + 6 + 6 + 84 + 402 + 71 + 0 + 88 = 666.

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 47 ways as a sum of consecutive naturals, for example, 3607933 + ... + 13279836.

It is an arithmetic number, because the mean of its divisors is an integer number (1078034175504).

Almost surely, 2^{81668440271088} is an apocalyptic number.

81668440271088 is a gapful number since it is divisible by the number (88) formed by its first and last digit.

It is an amenable number.

81668440271088 is an abundant number, since it is smaller than the sum of its proper divisors (177059761849872).

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

81668440271088 is a wasteful number, since it uses less digits than its factorization.

81668440271088 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16887908 (or 16887899 counting only the distinct ones).

The product of its (nonzero) digits is 33030144, while the sum is 63.

The spelling of 81668440271088 in words is "eighty-one trillion, six hundred sixty-eight billion, four hundred forty million, two hundred seventy-one thousand, eighty-eight".