66668888668289 has 2 divisors, whose sum is σ = 66668888668290. Its totient is φ = 66668888668288.

The previous prime is 66668888668279. The next prime is 66668888668309. The reversal of 66668888668289 is 98286688886666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49200292261264 + 17468596407025 = 7014292^2 + 4179545^2 .

It is a cyclic number.

It is not a de Polignac number, because 66668888668289 - 2³² = 66664593700993 is a prime.

It is not a weakly prime, because it can be changed into another prime (66668888668229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33334444334144 + 33334444334145.

It is an arithmetic number, because the mean of its divisors is an integer number (33334444334145).

Almost surely, 2^{66668888668289} is an apocalyptic number.

It is an amenable number.

66668888668289 is a deficient number, since it is larger than the sum of its proper divisors (1).

66668888668289 is an equidigital number, since it uses as much as digits as its factorization.

66668888668289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 220150628352, while the sum is 95.

The spelling of 66668888668289 in words is "sixty-six trillion, six hundred sixty-eight billion, eight hundred eighty-eight million, six hundred sixty-eight thousand, two hundred eighty-nine".