18442839 has 4 divisors (see below), whose sum is σ = 24590456. Its totient is φ = 12295224.

The previous prime is 18442817. The next prime is 18442859. The reversal of 18442839 is 93824481.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 18442839 - 2¹¹ = 18440791 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18442797 and 18442806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18442859) 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, 3073804 + ... + 3073809.

It is an arithmetic number, because the mean of its divisors is an integer number (6147614).

Almost surely, 2^18442839 is an apocalyptic number.

18442839 is a deficient number, since it is larger than the sum of its proper divisors (6147617).

18442839 is an equidigital number, since it uses as much as digits as its factorization.

18442839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6147616.

The product of its digits is 55296, while the sum is 39.

The square root of 18442839 is about 4294.5126615252. The cubic root of 18442839 is about 264.2059486852.

The spelling of 18442839 in words is "eighteen million, four hundred forty-two thousand, eight hundred thirty-nine".