81383744824 has 24 divisors (see below), whose sum is σ = 159236637480. Its totient is φ = 38920809840.

The previous prime is 81383744807. The next prime is 81383744839. The reversal of 81383744824 is 42844738318.

It is a congruent number.

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 5 ways as a sum of consecutive naturals, for example, 3859189 + ... + 3880219.

It is an arithmetic number, because the mean of its divisors is an integer number (6634859895).

Almost surely, 2^81383744824 is an apocalyptic number.

It is an amenable number.

81383744824 is a deficient number, since it is larger than the sum of its proper divisors (77852892656).

81383744824 is an frugal number, since it uses more digits than its factorization.

81383744824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42091 (or 21056 counting only the distinct ones).

The product of its digits is 4128768, while the sum is 52.

The spelling of 81383744824 in words is "eighty-one billion, three hundred eighty-three million, seven hundred forty-four thousand, eight hundred twenty-four".