81816010584 has 64 divisors (see below), whose sum is σ = 255010947840. Its totient is φ = 21250911360.

The previous prime is 81816010571. The next prime is 81816010607. The reversal of 81816010584 is 48501061818.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22134519 + ... + 22138214.

It is an arithmetic number, because the mean of its divisors is an integer number (3984546060).

Almost surely, 2^81816010584 is an apocalyptic number.

81816010584 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

81816010584 is an abundant number, since it is smaller than the sum of its proper divisors (173194937256).

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

81816010584 is a wasteful number, since it uses less digits than its factorization.

81816010584 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44272760 (or 44272756 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 42.

The spelling of 81816010584 in words is "eighty-one billion, eight hundred sixteen million, ten thousand, five hundred eighty-four".