66706978873 has 2 divisors, whose sum is σ = 66706978874. Its totient is φ = 66706978872.

The previous prime is 66706978859. The next prime is 66706978909. The reversal of 66706978873 is 37887960766.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44854156944 + 21852821929 = 211788^2 + 147827^2 .

It is a cyclic number.

It is not a de Polignac number, because 66706978873 - 2⁵ = 66706978841 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66706978799 and 66706978808.

It is not a weakly prime, because it can be changed into another prime (66706972873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33353489436 + 33353489437.

It is an arithmetic number, because the mean of its divisors is an integer number (33353489437).

Almost surely, 2^66706978873 is an apocalyptic number.

It is an amenable number.

66706978873 is a deficient number, since it is larger than the sum of its proper divisors (1).

66706978873 is an equidigital number, since it uses as much as digits as its factorization.

66706978873 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128024064, while the sum is 67.

The spelling of 66706978873 in words is "sixty-six billion, seven hundred six million, nine hundred seventy-eight thousand, eight hundred seventy-three".