81982645381833 has 32 divisors (see below), whose sum is σ = 128108888340480. Its totient is φ = 45668446158720.

The previous prime is 81982645381811. The next prime is 81982645381867. The reversal of 81982645381833 is 33818354628918.

It is not a de Polignac number, because 81982645381833 - 2²⁵ = 81982611827401 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81982645385833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 308771835 + ... + 309037232.

It is an arithmetic number, because the mean of its divisors is an integer number (4003402760640).

Almost surely, 2^{81982645381833} is an apocalyptic number.

It is an amenable number.

81982645381833 is a deficient number, since it is larger than the sum of its proper divisors (46126242958647).

81982645381833 is a wasteful number, since it uses less digits than its factorization.

81982645381833 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 617809237.

The product of its digits is 238878720, while the sum is 69.

The spelling of 81982645381833 in words is "eighty-one trillion, nine hundred eighty-two billion, six hundred forty-five million, three hundred eighty-one thousand, eight hundred thirty-three".