66866782208 has 42 divisors (see below), whose sum is σ = 133772224581. Its totient is φ = 33421688832.

The previous prime is 66866782187. The next prime is 66866782217. The reversal of 66866782208 is 80228766866.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 64784502784 + 2082279424 = 254528^2 + 45632^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=182848.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 23403116 + ... + 23405972.

Almost surely, 2^66866782208 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66866782208

66866782208 is an abundant number, since it is smaller than the sum of its proper divisors (66905442373).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66866782208 is an frugal number, since it uses more digits than its factorization.

66866782208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5740 (or 2859 counting only the distinct ones).

The product of its (nonzero) digits is 18579456, while the sum is 59.

The spelling of 66866782208 in words is "sixty-six billion, eight hundred sixty-six million, seven hundred eighty-two thousand, two hundred eight".