81653336018 has 8 divisors (see below), whose sum is σ = 122813738112. Its totient is φ = 40715423316.

The previous prime is 81653335999. The next prime is 81653336029. The reversal of 81653336018 is 81063335618.

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

It is a self number, because there is not a number n which added to its sum of digits gives 81653336018.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55621430 + ... + 55622897.

It is an arithmetic number, because the mean of its divisors is an integer number (15351717264).

Almost surely, 2^81653336018 is an apocalyptic number.

81653336018 is a deficient number, since it is larger than the sum of its proper divisors (41160402094).

81653336018 is a wasteful number, since it uses less digits than its factorization.

81653336018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111244696.

The product of its (nonzero) digits is 311040, while the sum is 44.

The spelling of 81653336018 in words is "eighty-one billion, six hundred fifty-three million, three hundred thirty-six thousand, eighteen".