81920784528 has 120 divisors (see below), whose sum is σ = 250176609696. Its totient is φ = 24817536000.

The previous prime is 81920784523. The next prime is 81920784529. The reversal of 81920784528 is 82548702918.

81920784528 is a `hidden beast` number, since 8 + 19 + 20 + 7 + 84 + 528 = 666.

It is a super-2 number, since 2×81920784528² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81920784523) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10214376 + ... + 10222392.

Almost surely, 2^81920784528 is an apocalyptic number.

81920784528 is a gapful number since it is divisible by the number (88) formed by its first and last digit.

It is an amenable number.

81920784528 is an abundant number, since it is smaller than the sum of its proper divisors (168255825168).

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

81920784528 is a wasteful number, since it uses less digits than its factorization.

81920784528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14493 (or 14484 counting only the distinct ones).

The product of its (nonzero) digits is 2580480, while the sum is 54.

The spelling of 81920784528 in words is "eighty-one billion, nine hundred twenty million, seven hundred eighty-four thousand, five hundred twenty-eight".