19611917307911 has 4 divisors (see below), whose sum is σ = 20765559502512. Its totient is φ = 18458275113312.

The previous prime is 19611917307901. The next prime is 19611917307929. The reversal of 19611917307911 is 11970371911691.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19611917307911 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19611917307901) 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 3 ways as a sum of consecutive naturals, for example, 576821097275 + ... + 576821097308.

It is an arithmetic number, because the mean of its divisors is an integer number (5191389875628).

Almost surely, 2^{19611917307911} is an apocalyptic number.

19611917307911 is a deficient number, since it is larger than the sum of its proper divisors (1153642194601).

19611917307911 is a wasteful number, since it uses less digits than its factorization.

19611917307911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1153642194600.

The product of its (nonzero) digits is 642978, while the sum is 56.

The spelling of 19611917307911 in words is "nineteen trillion, six hundred eleven billion, nine hundred seventeen million, three hundred seven thousand, nine hundred eleven".