66931975712669 has 2 divisors, whose sum is σ = 66931975712670. Its totient is φ = 66931975712668.

The previous prime is 66931975712611. The next prime is 66931975712677. The reversal of 66931975712669 is 96621757913966.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60295426890169 + 6636548822500 = 7765013^2 + 2576150^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66931975712669 is a prime.

It is a super-2 number, since 2×66931975712669² (a number of 28 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 66931975712669.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66931975712699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33465987856334 + 33465987856335.

It is an arithmetic number, because the mean of its divisors is an integer number (33465987856335).

Almost surely, 2^{66931975712669} is an apocalyptic number.

It is an amenable number.

66931975712669 is a deficient number, since it is larger than the sum of its proper divisors (1).

66931975712669 is an equidigital number, since it uses as much as digits as its factorization.

66931975712669 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1388832480, while the sum is 77.

The spelling of 66931975712669 in words is "sixty-six trillion, nine hundred thirty-one billion, nine hundred seventy-five million, seven hundred twelve thousand, six hundred sixty-nine".