81527209344 has 256 divisors, whose sum is σ = 275447001600. Its totient is φ = 23255009280.

The previous prime is 81527209277. The next prime is 81527209363. The reversal of 81527209344 is 44390272518.

81527209344 is a `hidden beast` number, since 81 + 5 + 27 + 209 + 344 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 81527209344.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16714234 + ... + 16719110.

It is an arithmetic number, because the mean of its divisors is an integer number (1075964850).

Almost surely, 2^81527209344 is an apocalyptic number.

81527209344 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81527209344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137723500800).

81527209344 is an abundant number, since it is smaller than the sum of its proper divisors (193919792256).

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

81527209344 is a wasteful number, since it uses less digits than its factorization.

81527209344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5598 (or 5580 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The spelling of 81527209344 in words is "eighty-one billion, five hundred twenty-seven million, two hundred nine thousand, three hundred forty-four".