18815066985 has 32 divisors (see below), whose sum is σ = 35367067008. Its totient is φ = 8420728320.

The previous prime is 18815066957. The next prime is 18815067059. The reversal of 18815066985 is 58966051881.

It is a happy number.

It is not a de Polignac number, because 18815066985 - 2¹⁰ = 18815065961 is a prime.

It is a Curzon number.

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 31 ways as a sum of consecutive naturals, for example, 4383652 + ... + 4387941.

It is an arithmetic number, because the mean of its divisors is an integer number (1105220844).

Almost surely, 2^18815066985 is an apocalyptic number.

18815066985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18815066985 is a deficient number, since it is larger than the sum of its proper divisors (16552000023).

18815066985 is a wasteful number, since it uses less digits than its factorization.

18815066985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8771625.

The product of its (nonzero) digits is 4147200, while the sum is 57.

The spelling of 18815066985 in words is "eighteen billion, eight hundred fifteen million, sixty-six thousand, nine hundred eighty-five".