1266709291817 has 2 divisors, whose sum is σ = 1266709291818. Its totient is φ = 1266709291816.

The previous prime is 1266709291711. The next prime is 1266709291831. The reversal of 1266709291817 is 7181929076621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 640401663001 + 626307628816 = 800251^2 + 791396^2 .

It is a cyclic number.

It is not a de Polignac number, because 1266709291817 - 2¹⁸ = 1266709029673 is a prime.

It is a super-2 number, since 2×1266709291817² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1266709291867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 633354645908 + 633354645909.

It is an arithmetic number, because the mean of its divisors is an integer number (633354645909).

Almost surely, 2^{1266709291817} is an apocalyptic number.

It is an amenable number.

1266709291817 is a deficient number, since it is larger than the sum of its proper divisors (1).

1266709291817 is an equidigital number, since it uses as much as digits as its factorization.

1266709291817 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4572288, while the sum is 59.

The spelling of 1266709291817 in words is "one trillion, two hundred sixty-six billion, seven hundred nine million, two hundred ninety-one thousand, eight hundred seventeen".