18813839 has 8 divisors (see below), whose sum is σ = 21416832. Its totient is φ = 16359640.

The previous prime is 18813811. The next prime is 18813863. The reversal of 18813839 is 93831881.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18813839 - 2²⁴ = 2036623 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18813796 and 18813805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18813239) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36929 + ... + 37434.

It is an arithmetic number, because the mean of its divisors is an integer number (2677104).

Almost surely, 2^18813839 is an apocalyptic number.

18813839 is a deficient number, since it is larger than the sum of its proper divisors (2602993).

18813839 is a wasteful number, since it uses less digits than its factorization.

18813839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74397.

The product of its digits is 41472, while the sum is 41.

The square root of 18813839 is about 4337.4922478317. The cubic root of 18813839 is about 265.9658076916.

The spelling of 18813839 in words is "eighteen million, eight hundred thirteen thousand, eight hundred thirty-nine".