81844515594 has 24 divisors (see below), whose sum is σ = 177837905700. Its totient is φ = 27203332608.

The previous prime is 81844515589. The next prime is 81844515601. The reversal of 81844515594 is 49551544818.

81844515594 is a `hidden beast` number, since 8 + 1 + 8 + 4 + 45 + 1 + 5 + 594 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 65759934969 + 16084580625 = 256437^2 + 126825^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 81844515594.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6507927 + ... + 6520490.

Almost surely, 2^81844515594 is an apocalyptic number.

81844515594 is an abundant number, since it is smaller than the sum of its proper divisors (95993390106).

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

81844515594 is a wasteful number, since it uses less digits than its factorization.

81844515594 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13028774 (or 13028771 counting only the distinct ones).

The product of its digits is 4608000, while the sum is 54.

The spelling of 81844515594 in words is "eighty-one billion, eight hundred forty-four million, five hundred fifteen thousand, five hundred ninety-four".