18398805 has 16 divisors (see below), whose sum is σ = 30234624. Its totient is φ = 9547200.

The previous prime is 18398767. The next prime is 18398813. The reversal of 18398805 is 50889381.

It is not a de Polignac number, because 18398805 - 2⁶ = 18398741 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16021 + ... + 17130.

It is an arithmetic number, because the mean of its divisors is an integer number (1889664).

Almost surely, 2^18398805 is an apocalyptic number.

18398805 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18398805 is a deficient number, since it is larger than the sum of its proper divisors (11835819).

18398805 is a wasteful number, since it uses less digits than its factorization.

18398805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33196.

The product of its (nonzero) digits is 69120, while the sum is 42.

The square root of 18398805 is about 4289.3828227380. The cubic root of 18398805 is about 263.9955089916.

The spelling of 18398805 in words is "eighteen million, three hundred ninety-eight thousand, eight hundred five".