17998859 has 2 divisors, whose sum is σ = 17998860. Its totient is φ = 17998858.

The previous prime is 17998847. The next prime is 17998861. The reversal of 17998859 is 95889971.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (95889971) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-17998859 is a prime.

Together with 17998861, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (17998819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8999429 + 8999430.

It is an arithmetic number, because the mean of its divisors is an integer number (8999430).

Almost surely, 2^17998859 is an apocalyptic number.

17998859 is a deficient number, since it is larger than the sum of its proper divisors (1).

17998859 is an equidigital number, since it uses as much as digits as its factorization.

17998859 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1632960, while the sum is 56.

The square root of 17998859 is about 4242.5062168487. The cubic root of 17998859 is about 262.0686017744.

The spelling of 17998859 in words is "seventeen million, nine hundred ninety-eight thousand, eight hundred fifty-nine".