66900639193 has 2 divisors, whose sum is σ = 66900639194. Its totient is φ = 66900639192.

The previous prime is 66900639191. The next prime is 66900639199. The reversal of 66900639193 is 39193600966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48844536064 + 18056103129 = 221008^2 + 134373^2 .

It is a cyclic number.

It is not a de Polignac number, because 66900639193 - 2¹ = 66900639191 is a prime.

Together with 66900639191, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 66900639193.

It is not a weakly prime, because it can be changed into another prime (66900639191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33450319596 + 33450319597.

It is an arithmetic number, because the mean of its divisors is an integer number (33450319597).

Almost surely, 2^66900639193 is an apocalyptic number.

It is an amenable number.

66900639193 is a deficient number, since it is larger than the sum of its proper divisors (1).

66900639193 is an equidigital number, since it uses as much as digits as its factorization.

66900639193 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1417176, while the sum is 52.

The spelling of 66900639193 in words is "sixty-six billion, nine hundred million, six hundred thirty-nine thousand, one hundred ninety-three".