18447216605 has 8 divisors (see below), whose sum is σ = 22137522264. Its totient is φ = 14757198400.

The previous prime is 18447216589. The next prime is 18447216611. The reversal of 18447216605 is 50661274481.

It can be written as a sum of positive squares in 4 ways, for example, as 2144523481 + 16302693124 = 46309^2 + 127682^2 .

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

It is not a de Polignac number, because 18447216605 - 2⁴ = 18447216589 is a prime.

It is a Duffinian number.

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 7 ways as a sum of consecutive naturals, for example, 112175 + ... + 222435.

It is an arithmetic number, because the mean of its divisors is an integer number (2767190283).

Almost surely, 2^18447216605 is an apocalyptic number.

It is an amenable number.

18447216605 is a deficient number, since it is larger than the sum of its proper divisors (3690305659).

18447216605 is a wasteful number, since it uses less digits than its factorization.

18447216605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143727.

The product of its (nonzero) digits is 322560, while the sum is 44.

The spelling of 18447216605 in words is "eighteen billion, four hundred forty-seven million, two hundred sixteen thousand, six hundred five".