18219839 has 8 divisors (see below), whose sum is σ = 19958400. Its totient is φ = 16495000.

The previous prime is 18219833. The next prime is 18219871. The reversal of 18219839 is 93891281.

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

It is a cyclic number.

It is not a de Polignac number, because 18219839 - 2⁸ = 18219583 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18219796 and 18219805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18219833) 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, 539 + ... + 6060.

It is an arithmetic number, because the mean of its divisors is an integer number (2494800).

Almost surely, 2^18219839 is an apocalyptic number.

18219839 is a deficient number, since it is larger than the sum of its proper divisors (1738561).

18219839 is a wasteful number, since it uses less digits than its factorization.

18219839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6861.

The product of its digits is 31104, while the sum is 41.

The square root of 18219839 is about 4268.4703349092. The cubic root of 18219839 is about 263.1367531795.

The spelling of 18219839 in words is "eighteen million, two hundred nineteen thousand, eight hundred thirty-nine".