81282557799 has 12 divisors (see below), whose sum is σ = 117412159176. Its totient is φ = 54186516432.

The previous prime is 81282557791. The next prime is 81282557831. The reversal of 81282557799 is 99775528218.

81282557799 is a `hidden beast` number, since 8 + 1 + 2 + 8 + 2 + 557 + 79 + 9 = 666.

It is not a de Polignac number, because 81282557799 - 2³ = 81282557791 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81282557791) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 155584 + ... + 432170.

It is an arithmetic number, because the mean of its divisors is an integer number (9784346598).

Almost surely, 2^81282557799 is an apocalyptic number.

81282557799 is a deficient number, since it is larger than the sum of its proper divisors (36129601377).

81282557799 is a wasteful number, since it uses less digits than its factorization.

81282557799 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309246 (or 309243 counting only the distinct ones).

The product of its digits is 25401600, while the sum is 63.

The spelling of 81282557799 in words is "eighty-one billion, two hundred eighty-two million, five hundred fifty-seven thousand, seven hundred ninety-nine".