81017751056 has 20 divisors (see below), whose sum is σ = 171242065104. Its totient is φ = 36826250400.

The previous prime is 81017751053. The next prime is 81017751077. The reversal of 81017751056 is 65015771018.

It is not an unprimeable number, because it can be changed into a prime (81017751053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 230163890 + ... + 230164241.

Almost surely, 2^81017751056 is an apocalyptic number.

It is an amenable number.

81017751056 is an abundant number, since it is smaller than the sum of its proper divisors (90224314048).

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

81017751056 is a wasteful number, since it uses less digits than its factorization.

81017751056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 460328150 (or 460328144 counting only the distinct ones).

The product of its (nonzero) digits is 58800, while the sum is 41.

The spelling of 81017751056 in words is "eighty-one billion, seventeen million, seven hundred fifty-one thousand, fifty-six".