81848684853 has 24 divisors (see below), whose sum is σ = 129064301912. Its totient is φ = 49678437888.

The previous prime is 81848684821. The next prime is 81848684893. The reversal of 81848684853 is 35848684818.

It can be written as a sum of positive squares in 4 ways, for example, as 24781686084 + 57066998769 = 157422^2 + 238887^2 .

It is not a de Polignac number, because 81848684853 - 2⁵ = 81848684821 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81848684893) 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 23 ways as a sum of consecutive naturals, for example, 4782976 + ... + 4800057.

Almost surely, 2^81848684853 is an apocalyptic number.

It is an amenable number.

81848684853 is a deficient number, since it is larger than the sum of its proper divisors (47215617059).

81848684853 is a wasteful number, since it uses less digits than its factorization.

81848684853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9583125 (or 9583122 counting only the distinct ones).

The product of its digits is 47185920, while the sum is 63.

The spelling of 81848684853 in words is "eighty-one billion, eight hundred forty-eight million, six hundred eighty-four thousand, eight hundred fifty-three".