16661121417361 has 2 divisors, whose sum is σ = 16661121417362. Its totient is φ = 16661121417360.

The previous prime is 16661121417293. The next prime is 16661121417407. The reversal of 16661121417361 is 16371412116661.

It is an a-pointer prime, because the next prime (16661121417407) can be obtained adding 16661121417361 to its sum of digits (46).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9050590896400 + 7610530520961 = 3008420^2 + 2758719^2 .

It is a cyclic number.

It is not a de Polignac number, because 16661121417361 - 2¹⁹ = 16661120893073 is a prime.

It is not a weakly prime, because it can be changed into another prime (16661121417761) 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, 8330560708680 + 8330560708681.

It is an arithmetic number, because the mean of its divisors is an integer number (8330560708681).

Almost surely, 2^{16661121417361} is an apocalyptic number.

It is an amenable number.

16661121417361 is a deficient number, since it is larger than the sum of its proper divisors (1).

16661121417361 is an equidigital number, since it uses as much as digits as its factorization.

16661121417361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 217728, while the sum is 46.

The spelling of 16661121417361 in words is "sixteen trillion, six hundred sixty-one billion, one hundred twenty-one million, four hundred seventeen thousand, three hundred sixty-one".