81983518345 has 16 divisors (see below), whose sum is σ = 99642332160. Its totient is φ = 64745688384.

The previous prime is 81983518343. The next prime is 81983518349. The reversal of 81983518345 is 54381538918.

It is a cyclic number.

It is not a de Polignac number, because 81983518345 - 2¹ = 81983518343 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81983518343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2977632 + ... + 3005038.

It is an arithmetic number, because the mean of its divisors is an integer number (6227645760).

Almost surely, 2^81983518345 is an apocalyptic number.

It is an amenable number.

81983518345 is a deficient number, since it is larger than the sum of its proper divisors (17658813815).

81983518345 is a wasteful number, since it uses less digits than its factorization.

81983518345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35064.

The product of its digits is 4147200, while the sum is 55.

The spelling of 81983518345 in words is "eighty-one billion, nine hundred eighty-three million, five hundred eighteen thousand, three hundred forty-five".