66688822778833 has 2 divisors, whose sum is σ = 66688822778834. Its totient is φ = 66688822778832.

The previous prime is 66688822778827. The next prime is 66688822778843. The reversal of 66688822778833 is 33887722888666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60261948802449 + 6426873976384 = 7762857^2 + 2535128^2 .

It is a cyclic number.

It is not a de Polignac number, because 66688822778833 - 2²⁵ = 66688789224401 is a prime.

It is a zygodrome in base 10.

It is not a weakly prime, because it can be changed into another prime (66688822778843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33344411389416 + 33344411389417.

It is an arithmetic number, because the mean of its divisors is an integer number (33344411389417).

Almost surely, 2^{66688822778833} is an apocalyptic number.

It is an amenable number.

66688822778833 is a deficient number, since it is larger than the sum of its proper divisors (1).

66688822778833 is an equidigital number, since it uses as much as digits as its factorization.

66688822778833 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12485394432, while the sum is 82.

The spelling of 66688822778833 in words is "sixty-six trillion, six hundred eighty-eight billion, eight hundred twenty-two million, seven hundred seventy-eight thousand, eight hundred thirty-three".