211566404666 has 8 divisors (see below), whose sum is σ = 317519227584. Its totient is φ = 105726662140.

The previous prime is 211566404617. The next prime is 211566404681. The reversal of 211566404666 is 666404665112.

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

It is a self number, because there is not a number n which added to its sum of digits gives 211566404666.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28265420 + ... + 28272903.

It is an arithmetic number, because the mean of its divisors is an integer number (39689903448).

Almost surely, 2^211566404666 is an apocalyptic number.

211566404666 is a deficient number, since it is larger than the sum of its proper divisors (105952822918).

211566404666 is a wasteful number, since it uses less digits than its factorization.

211566404666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56540196.

The product of its (nonzero) digits is 1244160, while the sum is 47.

The spelling of 211566404666 in words is "two hundred eleven billion, five hundred sixty-six million, four hundred four thousand, six hundred sixty-six".