18508999 has 4 divisors (see below), whose sum is σ = 18960480. Its totient is φ = 18057520.

The previous prime is 18508993. The next prime is 18509003. The reversal of 18508999 is 99980581.

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: 99980581 = 73 ⋅1369597.

It is a cyclic number.

It is not a de Polignac number, because 18508999 - 2⁷ = 18508871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18508993) 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, 225679 + ... + 225760.

It is an arithmetic number, because the mean of its divisors is an integer number (4740120).

Almost surely, 2^18508999 is an apocalyptic number.

18508999 is a deficient number, since it is larger than the sum of its proper divisors (451481).

18508999 is an equidigital number, since it uses as much as digits as its factorization.

18508999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451480.

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

The square root of 18508999 is about 4302.2086188375. The cubic root of 18508999 is about 264.5215003433.

The spelling of 18508999 in words is "eighteen million, five hundred eight thousand, nine hundred ninety-nine".