66864490879 has 2 divisors, whose sum is σ = 66864490880. Its totient is φ = 66864490878.

The previous prime is 66864490877. The next prime is 66864490883. The reversal of 66864490879 is 97809446866.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66864490879 - 2¹ = 66864490877 is a prime.

Together with 66864490877, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66864490877) 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, 33432245439 + 33432245440.

It is an arithmetic number, because the mean of its divisors is an integer number (33432245440).

Almost surely, 2^66864490879 is an apocalyptic number.

66864490879 is a deficient number, since it is larger than the sum of its proper divisors (1).

66864490879 is an equidigital number, since it uses as much as digits as its factorization.

66864490879 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 125411328, while the sum is 67.

The spelling of 66864490879 in words is "sixty-six billion, eight hundred sixty-four million, four hundred ninety thousand, eight hundred seventy-nine".