68565056561 has 2 divisors, whose sum is σ = 68565056562. Its totient is φ = 68565056560.

The previous prime is 68565056543. The next prime is 68565056587. The reversal of 68565056561 is 16565056586.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68539240000 + 25816561 = 261800^2 + 5081^2 .

It is a cyclic number.

It is not a de Polignac number, because 68565056561 - 2¹⁴ = 68565040177 is a prime.

It is not a weakly prime, because it can be changed into another prime (68565056501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34282528280 + 34282528281.

It is an arithmetic number, because the mean of its divisors is an integer number (34282528281).

Almost surely, 2^68565056561 is an apocalyptic number.

It is an amenable number.

68565056561 is a deficient number, since it is larger than the sum of its proper divisors (1).

68565056561 is an equidigital number, since it uses as much as digits as its factorization.

68565056561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480000, while the sum is 53.

The spelling of 68565056561 in words is "sixty-eight billion, five hundred sixty-five million, fifty-six thousand, five hundred sixty-one".