81043813808 has 80 divisors (see below), whose sum is σ = 164402810880. Its totient is φ = 38664235008.

The previous prime is 81043813789. The next prime is 81043813811. The reversal of 81043813808 is 80831834018.

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, 19625888 + ... + 19630016.

It is an arithmetic number, because the mean of its divisors is an integer number (2055035136).

Almost surely, 2^81043813808 is an apocalyptic number.

It is an amenable number.

81043813808 is an abundant number, since it is smaller than the sum of its proper divisors (83358997072).

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

81043813808 is a wasteful number, since it uses less digits than its factorization.

81043813808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4834 (or 4828 counting only the distinct ones).

The product of its (nonzero) digits is 147456, while the sum is 44.

The spelling of 81043813808 in words is "eighty-one billion, forty-three million, eight hundred thirteen thousand, eight hundred eight".