19621840239 has 6 divisors (see below), whose sum is σ = 28342658136. Its totient is φ = 13081226820.

The previous prime is 19621840193. The next prime is 19621840241. The reversal of 19621840239 is 93204812691.

19621840239 is a `hidden beast` number, since 19 + 621 + 8 + 4 + 0 + 2 + 3 + 9 = 666.

It is not a de Polignac number, because 19621840239 - 2¹¹ = 19621838191 is a prime.

It is a super-2 number, since 2×19621840239² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 19621840194 and 19621840203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19621840289) 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 5 ways as a sum of consecutive naturals, for example, 1090102227 + ... + 1090102244.

It is an arithmetic number, because the mean of its divisors is an integer number (4723776356).

Almost surely, 2^19621840239 is an apocalyptic number.

19621840239 is a deficient number, since it is larger than the sum of its proper divisors (8720817897).

19621840239 is a wasteful number, since it uses less digits than its factorization.

19621840239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2180204477 (or 2180204474 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The spelling of 19621840239 in words is "nineteen billion, six hundred twenty-one million, eight hundred forty thousand, two hundred thirty-nine".