18851803985 has 16 divisors (see below), whose sum is σ = 25893893376. Its totient is φ = 12906955968.

The previous prime is 18851803981. The next prime is 18851804017. The reversal of 18851803985 is 58930815881.

It is a cyclic number.

It is not a de Polignac number, because 18851803985 - 2² = 18851803981 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18851803985.

It is not an unprimeable number, because it can be changed into a prime (18851803981) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 393602 + ... + 438891.

It is an arithmetic number, because the mean of its divisors is an integer number (1618368336).

Almost surely, 2^18851803985 is an apocalyptic number.

It is an amenable number.

18851803985 is a deficient number, since it is larger than the sum of its proper divisors (7042089391).

18851803985 is an equidigital number, since it uses as much as digits as its factorization.

18851803985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 833152.

The product of its (nonzero) digits is 2764800, while the sum is 56.

The spelling of 18851803985 in words is "eighteen billion, eight hundred fifty-one million, eight hundred three thousand, nine hundred eighty-five".