81162885808 has 20 divisors (see below), whose sum is σ = 165529570360. Its totient is φ = 38445577344.

The previous prime is 81162885733. The next prime is 81162885809. The reversal of 81162885808 is 80858826118.

It is not an unprimeable number, because it can be changed into a prime (81162885809) 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, 133491285 + ... + 133491892.

It is an arithmetic number, because the mean of its divisors is an integer number (8276478518).

Almost surely, 2^81162885808 is an apocalyptic number.

It is an amenable number.

81162885808 is an abundant number, since it is smaller than the sum of its proper divisors (84366684552).

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

81162885808 is a wasteful number, since it uses less digits than its factorization.

81162885808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266983204 (or 266983198 counting only the distinct ones).

The product of its (nonzero) digits is 1966080, while the sum is 55.

The spelling of 81162885808 in words is "eighty-one billion, one hundred sixty-two million, eight hundred eighty-five thousand, eight hundred eight".