19855259 has 2 divisors, whose sum is σ = 19855260. Its totient is φ = 19855258.

The previous prime is 19855243. The next prime is 19855271. The reversal of 19855259 is 95255891.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 19855259 - 2⁴ = 19855243 is a prime.

It is a super-5 number, since 5×19855259⁵ (a number of 38 digits) contains 55555 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19855219) 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, 9927629 + 9927630.

It is an arithmetic number, because the mean of its divisors is an integer number (9927630).

Almost surely, 2^19855259 is an apocalyptic number.

19855259 is a deficient number, since it is larger than the sum of its proper divisors (1).

19855259 is an equidigital number, since it uses as much as digits as its factorization.

19855259 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 162000, while the sum is 44.

The square root of 19855259 is about 4455.9240343614. The cubic root of 19855259 is about 270.7853631069.

The spelling of 19855259 in words is "nineteen million, eight hundred fifty-five thousand, two hundred fifty-nine".