66844426193 has 2 divisors, whose sum is σ = 66844426194. Its totient is φ = 66844426192.

The previous prime is 66844426163. The next prime is 66844426237. The reversal of 66844426193 is 39162444866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65529856144 + 1314570049 = 255988^2 + 36257^2 .

It is a cyclic number.

It is not a de Polignac number, because 66844426193 - 2⁸ = 66844425937 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (66844426153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33422213096 + 33422213097.

It is an arithmetic number, because the mean of its divisors is an integer number (33422213097).

Almost surely, 2^66844426193 is an apocalyptic number.

It is an amenable number.

66844426193 is a deficient number, since it is larger than the sum of its proper divisors (1).

66844426193 is an equidigital number, since it uses as much as digits as its factorization.

66844426193 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5971968, while the sum is 53.

The spelling of 66844426193 in words is "sixty-six billion, eight hundred forty-four million, four hundred twenty-six thousand, one hundred ninety-three".