8517161766661 has 2 divisors, whose sum is σ = 8517161766662. Its totient is φ = 8517161766660.

The previous prime is 8517161766637. The next prime is 8517161766719. The reversal of 8517161766661 is 1666671617158.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5303836636036 + 3213325130625 = 2303006^2 + 1792575^2 .

It is a cyclic number.

It is not a de Polignac number, because 8517161766661 - 2⁹ = 8517161766149 is a prime.

It is a super-2 number, since 2×8517161766661² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 8517161766661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8517161767661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4258580883330 + 4258580883331.

It is an arithmetic number, because the mean of its divisors is an integer number (4258580883331).

Almost surely, 2^{8517161766661} is an apocalyptic number.

It is an amenable number.

8517161766661 is a deficient number, since it is larger than the sum of its proper divisors (1).

8517161766661 is an equidigital number, since it uses as much as digits as its factorization.

8517161766661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15240960, while the sum is 61.

The spelling of 8517161766661 in words is "eight trillion, five hundred seventeen billion, one hundred sixty-one million, seven hundred sixty-six thousand, six hundred sixty-one".