81982645381834 has 8 divisors (see below), whose sum is σ = 126297588831588. Its totient is φ = 39883449104640.

The previous prime is 81982645381811. The next prime is 81982645381867. The reversal of 81982645381834 is 43818354628918.

It can be written as a sum of positive squares in 2 ways, for example, as 81108990638809 + 873654743025 = 9006053^2 + 934695^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 553936793047 + ... + 553936793194.

Almost surely, 2^{81982645381834} is an apocalyptic number.

81982645381834 is a deficient number, since it is larger than the sum of its proper divisors (44314943449754).

81982645381834 is a wasteful number, since it uses less digits than its factorization.

81982645381834 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1107873586280.

The product of its digits is 318504960, while the sum is 70.

The spelling of 81982645381834 in words is "eighty-one trillion, nine hundred eighty-two billion, six hundred forty-five million, three hundred eighty-one thousand, eight hundred thirty-four".