19743209795849 has 2 divisors, whose sum is σ = 19743209795850. Its totient is φ = 19743209795848.

The previous prime is 19743209795753. The next prime is 19743209795867. The reversal of 19743209795849 is 94859790234791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19591290702025 + 151919093824 = 4426205^2 + 389768^2 .

It is a cyclic number.

It is not a de Polignac number, because 19743209795849 - 2²⁸ = 19742941360393 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19743209795849.

It is not a weakly prime, because it can be changed into another prime (19743209095849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9871604897924 + 9871604897925.

It is an arithmetic number, because the mean of its divisors is an integer number (9871604897925).

Almost surely, 2^{19743209795849} is an apocalyptic number.

It is an amenable number.

19743209795849 is a deficient number, since it is larger than the sum of its proper divisors (1).

19743209795849 is an equidigital number, since it uses as much as digits as its factorization.

19743209795849 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1234517760, while the sum is 77.

The spelling of 19743209795849 in words is "nineteen trillion, seven hundred forty-three billion, two hundred nine million, seven hundred ninety-five thousand, eight hundred forty-nine".