6561768944117 has 2 divisors, whose sum is σ = 6561768944118. Its totient is φ = 6561768944116.

The previous prime is 6561768944053. The next prime is 6561768944141. The reversal of 6561768944117 is 7114498671656.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6517405632241 + 44363311876 = 2552921^2 + 210626^2 .

It is a cyclic number.

It is not a de Polignac number, because 6561768944117 - 2⁶ = 6561768944053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6561768944167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3280884472058 + 3280884472059.

It is an arithmetic number, because the mean of its divisors is an integer number (3280884472059).

Almost surely, 2^{6561768944117} is an apocalyptic number.

It is an amenable number.

6561768944117 is a deficient number, since it is larger than the sum of its proper divisors (1).

6561768944117 is an equidigital number, since it uses as much as digits as its factorization.

6561768944117 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 60963840, while the sum is 65.

The spelling of 6561768944117 in words is "six trillion, five hundred sixty-one billion, seven hundred sixty-eight million, nine hundred forty-four thousand, one hundred seventeen".