66859000661 has 8 divisors (see below), whose sum is σ = 66915340800. Its totient is φ = 66802688640.

The previous prime is 66859000639. The next prime is 66859000693. The reversal of 66859000661 is 16600095866.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66859000661 - 2¹⁸ = 66858738517 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66859000601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8188421 + ... + 8196581.

It is an arithmetic number, because the mean of its divisors is an integer number (8364417600).

Almost surely, 2^66859000661 is an apocalyptic number.

66859000661 is the 115637-th centered decagonal number.

It is an amenable number.

66859000661 is a deficient number, since it is larger than the sum of its proper divisors (56340139).

66859000661 is a wasteful number, since it uses less digits than its factorization.

66859000661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14059.

The product of its (nonzero) digits is 466560, while the sum is 47.

The spelling of 66859000661 in words is "sixty-six billion, eight hundred fifty-nine million, six hundred sixty-one", and thus it is an aban number.