19705981749673 has 8 divisors (see below), whose sum is σ = 19741964668200. Its totient is φ = 19670030919168.

The previous prime is 19705981749661. The next prime is 19705981749703. The reversal of 19705981749673 is 37694718950791.

It can be written as a sum of positive squares in 4 ways, for example, as 9472655861824 + 10233325887849 = 3077768^2 + 3198957^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19705981749673 - 2⁴¹ = 17506958494121 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19705981749673.

It is not an unprimeable number, because it can be changed into a prime (19705981749473) 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 in 7 ways as a sum of consecutive naturals, for example, 6792468 + ... + 9249301.

It is an arithmetic number, because the mean of its divisors is an integer number (2467745583525).

Almost surely, 2^{19705981749673} is an apocalyptic number.

It is an amenable number.

19705981749673 is a deficient number, since it is larger than the sum of its proper divisors (35982918527).

19705981749673 is a wasteful number, since it uses less digits than its factorization.

19705981749673 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16044011.

The product of its (nonzero) digits is 720135360, while the sum is 76.

The spelling of 19705981749673 in words is "nineteen trillion, seven hundred five billion, nine hundred eighty-one million, seven hundred forty-nine thousand, six hundred seventy-three".