18099859 has 4 divisors (see below), whose sum is σ = 18396640. Its totient is φ = 17803080.

The previous prime is 18099853. The next prime is 18099869. The reversal of 18099859 is 95899081.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 95899081 = 677 ⋅141653.

It is a cyclic number.

It is not a de Polignac number, because 18099859 - 2¹¹ = 18097811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18099853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 148299 + ... + 148420.

It is an arithmetic number, because the mean of its divisors is an integer number (4599160).

Almost surely, 2^18099859 is an apocalyptic number.

18099859 is a deficient number, since it is larger than the sum of its proper divisors (296781).

18099859 is an equidigital number, since it uses as much as digits as its factorization.

18099859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296780.

The product of its (nonzero) digits is 233280, while the sum is 49.

The square root of 18099859 is about 4254.3929061618. The cubic root of 18099859 is about 262.5578841360.

The spelling of 18099859 in words is "eighteen million, ninety-nine thousand, eight hundred fifty-nine".