81728844088 has 32 divisors (see below), whose sum is σ = 162287336160. Its totient is φ = 38453155840.

The previous prime is 81728844047. The next prime is 81728844089. The reversal of 81728844088 is 88044882718.

It is a super-2 number, since 2×81728844088² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81728844089) 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 7 ways as a sum of consecutive naturals, for example, 677733 + ... + 789163.

It is an arithmetic number, because the mean of its divisors is an integer number (5071479255).

Almost surely, 2^81728844088 is an apocalyptic number.

It is an amenable number.

81728844088 is a deficient number, since it is larger than the sum of its proper divisors (80558492072).

81728844088 is a wasteful number, since it uses less digits than its factorization.

81728844088 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116847 (or 116843 counting only the distinct ones).

The product of its (nonzero) digits is 7340032, while the sum is 58.

The spelling of 81728844088 in words is "eighty-one billion, seven hundred twenty-eight million, eight hundred forty-four thousand, eighty-eight".