81144444116 has 6 divisors (see below), whose sum is σ = 142002777210. Its totient is φ = 40572222056.

The previous prime is 81144444083. The next prime is 81144444119. The reversal of 81144444116 is 61144444118.

It can be written as a sum of positive squares in only one way, i.e., 57782544400 + 23361899716 = 240380^2 + 152846^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 81144444116.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81144444119) 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 as a sum of consecutive naturals, namely, 10143055511 + ... + 10143055518.

It is an arithmetic number, because the mean of its divisors is an integer number (23667129535).

Almost surely, 2^81144444116 is an apocalyptic number.

It is an amenable number.

81144444116 is a deficient number, since it is larger than the sum of its proper divisors (60858333094).

81144444116 is a wasteful number, since it uses less digits than its factorization.

81144444116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20286111033 (or 20286111031 counting only the distinct ones).

The product of its digits is 49152, while the sum is 38.

The spelling of 81144444116 in words is "eighty-one billion, one hundred forty-four million, four hundred forty-four thousand, one hundred sixteen".