18143899 has 4 divisors (see below), whose sum is σ = 18223360. Its totient is φ = 18064440.

The previous prime is 18143891. The next prime is 18143903. The reversal of 18143899 is 99834181.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18143899 - 2³ = 18143891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18143891) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 39387 + ... + 39844.

It is an arithmetic number, because the mean of its divisors is an integer number (4555840).

Almost surely, 2^18143899 is an apocalyptic number.

18143899 is a deficient number, since it is larger than the sum of its proper divisors (79461).

18143899 is an equidigital number, since it uses as much as digits as its factorization.

18143899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79460.

The product of its digits is 62208, while the sum is 43.

The square root of 18143899 is about 4259.5655881792. The cubic root of 18143899 is about 262.7706608136.

The spelling of 18143899 in words is "eighteen million, one hundred forty-three thousand, eight hundred ninety-nine".