81443688480 has 1152 divisors, whose sum is σ = 370828523520. Its totient is φ = 15765995520.

The previous prime is 81443688463. The next prime is 81443688493. The reversal of 81443688480 is 8488634418.

81443688480 is a `hidden beast` number, since 81 + 4 + 4 + 3 + 6 + 88 + 480 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 141149952 + ... + 141150528.

It is an arithmetic number, because the mean of its divisors is an integer number (321899760).

Almost surely, 2^81443688480 is an apocalyptic number.

81443688480 is a gapful number since it is divisible by the number (80) 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 81443688480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (185414261760).

81443688480 is an abundant number, since it is smaller than the sum of its proper divisors (289384835040).

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

81443688480 is a wasteful number, since it uses less digits than its factorization.

81443688480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 702 (or 691 counting only the distinct ones).

The product of its (nonzero) digits is 4718592, while the sum is 54.

The spelling of 81443688480 in words is "eighty-one billion, four hundred forty-three million, six hundred eighty-eight thousand, four hundred eighty".