18819959 has 2 divisors, whose sum is σ = 18819960. Its totient is φ = 18819958.

The previous prime is 18819953. The next prime is 18819961. The reversal of 18819959 is 95991881.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18819959 - 2¹⁶ = 18754423 is a prime.

Together with 18819961, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18819953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9409979 + 9409980.

It is an arithmetic number, because the mean of its divisors is an integer number (9409980).

Almost surely, 2^18819959 is an apocalyptic number.

18819959 is a deficient number, since it is larger than the sum of its proper divisors (1).

18819959 is an equidigital number, since it uses as much as digits as its factorization.

18819959 is an evil number, because the sum of its binary digits is even.

The product of its digits is 233280, while the sum is 50.

The square root of 18819959 is about 4338.1976672346. The cubic root of 18819959 is about 265.9946434559.

The spelling of 18819959 in words is "eighteen million, eight hundred nineteen thousand, nine hundred fifty-nine".