561666290766157 has 2 divisors, whose sum is σ = 561666290766158. Its totient is φ = 561666290766156.

The previous prime is 561666290765977. The next prime is 561666290766199. The reversal of 561666290766157 is 751667092666165.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 468929756705796 + 92736534060361 = 21654786^2 + 9629981^2 .

It is a cyclic number.

It is not a de Polignac number, because 561666290766157 - 2⁴⁷ = 420928802410829 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 561666290766157.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (561666290763157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280833145383078 + 280833145383079.

It is an arithmetic number, because the mean of its divisors is an integer number (280833145383079).

Almost surely, 2^{561666290766157} is an apocalyptic number.

It is an amenable number.

561666290766157 is a deficient number, since it is larger than the sum of its proper divisors (1).

561666290766157 is an equidigital number, since it uses as much as digits as its factorization.

561666290766157 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1028764800, while the sum is 73.

The spelling of 561666290766157 in words is "five hundred sixty-one trillion, six hundred sixty-six billion, two hundred ninety million, seven hundred sixty-six thousand, one hundred fifty-seven".