18398839 has 4 divisors (see below), whose sum is σ = 18495360. Its totient is φ = 18302320.

The previous prime is 18398837. The next prime is 18398843. The reversal of 18398839 is 93889381.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93889381 = 23 ⋅4082147.

It is a cyclic number.

It is not a de Polignac number, because 18398839 - 2¹ = 18398837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18398792 and 18398801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18398833) 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, 47974 + ... + 48355.

It is an arithmetic number, because the mean of its divisors is an integer number (4623840).

Almost surely, 2^18398839 is an apocalyptic number.

18398839 is a deficient number, since it is larger than the sum of its proper divisors (96521).

18398839 is an equidigital number, since it uses as much as digits as its factorization.

18398839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96520.

The product of its digits is 373248, while the sum is 49.

The square root of 18398839 is about 4289.3867860103. The cubic root of 18398839 is about 263.9956716079.

The spelling of 18398839 in words is "eighteen million, three hundred ninety-eight thousand, eight hundred thirty-nine".