6666168561 has 8 divisors (see below), whose sum is σ = 9571934400. Its totient is φ = 4102257552.

The previous prime is 6666168547. The next prime is 6666168577. The reversal of 6666168561 is 1658616666.

6666168561 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 6666168561 - 2¹¹ = 6666166513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6666168541) 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 in 7 ways as a sum of consecutive naturals, for example, 85463661 + ... + 85463738.

It is an arithmetic number, because the mean of its divisors is an integer number (1196491800).

Almost surely, 2^6666168561 is an apocalyptic number.

It is an amenable number.

6666168561 is a deficient number, since it is larger than the sum of its proper divisors (2905765839).

6666168561 is a wasteful number, since it uses less digits than its factorization.

6666168561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170927415.

The product of its digits is 1866240, while the sum is 51.

The square root of 6666168561 is about 81646.6077739914. The cubic root of 6666168561 is about 1882.0251830568.

The spelling of 6666168561 in words is "six billion, six hundred sixty-six million, one hundred sixty-eight thousand, five hundred sixty-one".