19839855 has 24 divisors (see below), whose sum is σ = 36927792. Its totient is φ = 9069312.

The previous prime is 19839851. The next prime is 19839863. The reversal of 19839855 is 55893891.

It is not a de Polignac number, because 19839855 - 2² = 19839851 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19839851) 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 in 23 ways as a sum of consecutive naturals, for example, 12762 + ... + 14231.

It is an arithmetic number, because the mean of its divisors is an integer number (1538658).

Almost surely, 2^19839855 is an apocalyptic number.

19839855 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

19839855 is a deficient number, since it is larger than the sum of its proper divisors (17087937).

19839855 is a wasteful number, since it uses less digits than its factorization.

19839855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27015 (or 27008 counting only the distinct ones).

The product of its digits is 388800, while the sum is 48.

The square root of 19839855 is about 4454.1952135038. The cubic root of 19839855 is about 270.7153185763.

The spelling of 19839855 in words is "nineteen million, eight hundred thirty-nine thousand, eight hundred fifty-five".