18839389 has 2 divisors, whose sum is σ = 18839390. Its totient is φ = 18839388.

The previous prime is 18839371. The next prime is 18839399. The reversal of 18839389 is 98393881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12131289 + 6708100 = 3483^2 + 2590^2 .

It is an emirp because it is prime and its reverse (98393881) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18839389 - 2¹⁵ = 18806621 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18839399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9419694 + 9419695.

It is an arithmetic number, because the mean of its divisors is an integer number (9419695).

Almost surely, 2^18839389 is an apocalyptic number.

It is an amenable number.

18839389 is a deficient number, since it is larger than the sum of its proper divisors (1).

18839389 is an equidigital number, since it uses as much as digits as its factorization.

18839389 is an odious number, because the sum of its binary digits is odd.

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

The square root of 18839389 is about 4340.4364987867. The cubic root of 18839389 is about 266.0861508877.

The spelling of 18839389 in words is "eighteen million, eight hundred thirty-nine thousand, three hundred eighty-nine".