81081100833608 has 64 divisors (see below), whose sum is σ = 162823326994800. Its totient is φ = 37716701552640.

The previous prime is 81081100833571. The next prime is 81081100833617. The reversal of 81081100833608 is 80633800118018.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 37412820026404 + 43668280807204 = 6116602^2 + 6608198^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43101338 + ... + 44943158.

Almost surely, 2^{81081100833608} is an apocalyptic number.

It is an amenable number.

81081100833608 is an abundant number, since it is smaller than the sum of its proper divisors (81742226161192).

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

81081100833608 is a wasteful number, since it uses less digits than its factorization.

81081100833608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1845570 (or 1845566 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 47.

The spelling of 81081100833608 in words is "eighty-one trillion, eighty-one billion, one hundred million, eight hundred thirty-three thousand, six hundred eight".