81750065760 has 576 divisors, whose sum is σ = 327852645120. Its totient is φ = 18335600640.

The previous prime is 81750065759. The next prime is 81750065773. The reversal of 81750065760 is 6756005718.

81750065760 is a `hidden beast` number, since 8 + 1 + 75 + 0 + 0 + 6 + 576 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 12938122 + ... + 12944438.

It is an arithmetic number, because the mean of its divisors is an integer number (569188620).

Almost surely, 2^81750065760 is an apocalyptic number.

81750065760 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 81750065760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (163926322560).

81750065760 is an abundant number, since it is smaller than the sum of its proper divisors (246102579360).

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

81750065760 is a wasteful number, since it uses less digits than its factorization.

81750065760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6411 (or 6400 counting only the distinct ones).

The product of its (nonzero) digits is 352800, while the sum is 45.

The spelling of 81750065760 in words is "eighty-one billion, seven hundred fifty million, sixty-five thousand, seven hundred sixty".