18998313 has 4 divisors (see below), whose sum is σ = 25331088. Its totient is φ = 12665540.

The previous prime is 18998281. The next prime is 18998321. The reversal of 18998313 is 31389981.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18998313 - 2⁵ = 18998281 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18998363) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3166383 + ... + 3166388.

It is an arithmetic number, because the mean of its divisors is an integer number (6332772).

Almost surely, 2^18998313 is an apocalyptic number.

It is an amenable number.

18998313 is a deficient number, since it is larger than the sum of its proper divisors (6332775).

18998313 is an equidigital number, since it uses as much as digits as its factorization.

18998313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6332774.

The product of its digits is 46656, while the sum is 42.

The square root of 18998313 is about 4358.7054270735. The cubic root of 18998313 is about 266.8322671058.

The spelling of 18998313 in words is "eighteen million, nine hundred ninety-eight thousand, three hundred thirteen".