66874378842389 has 2 divisors, whose sum is σ = 66874378842390. Its totient is φ = 66874378842388.

The previous prime is 66874378842347. The next prime is 66874378842433. The reversal of 66874378842389 is 98324887347866.

66874378842389 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38180251086289 + 28694127756100 = 6179017^2 + 5356690^2 .

It is a cyclic number.

It is not a de Polignac number, because 66874378842389 - 2¹⁶ = 66874378776853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66874378842329) 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, 33437189421194 + 33437189421195.

It is an arithmetic number, because the mean of its divisors is an integer number (33437189421195).

Almost surely, 2^{66874378842389} is an apocalyptic number.

It is an amenable number.

66874378842389 is a deficient number, since it is larger than the sum of its proper divisors (1).

66874378842389 is an equidigital number, since it uses as much as digits as its factorization.

66874378842389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18728091648, while the sum is 83.

The spelling of 66874378842389 in words is "sixty-six trillion, eight hundred seventy-four billion, three hundred seventy-eight million, eight hundred forty-two thousand, three hundred eighty-nine".