81017775108 has 36 divisors (see below), whose sum is σ = 207851578480. Its totient is φ = 26602850736.

The previous prime is 81017775061. The next prime is 81017775121. The reversal of 81017775108 is 80157771018.

It is a tau number, because it is divible by the number of its divisors (36).

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 11 ways as a sum of consecutive naturals, for example, 16792318 + ... + 16797141.

Almost surely, 2^81017775108 is an apocalyptic number.

It is an amenable number.

81017775108 is an abundant number, since it is smaller than the sum of its proper divisors (126833803372).

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

81017775108 is a wasteful number, since it uses less digits than its factorization.

81017775108 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33589536 (or 33589531 counting only the distinct ones).

The product of its (nonzero) digits is 109760, while the sum is 45.

The spelling of 81017775108 in words is "eighty-one billion, seventeen million, seven hundred seventy-five thousand, one hundred eight".