211105666 has 8 divisors (see below), whose sum is σ = 317352780. Its totient is φ = 105321408.

The previous prime is 211105663. The next prime is 211105673. The reversal of 211105666 is 666501112.

It can be written as a sum of positive squares in 2 ways, for example, as 205205625 + 5900041 = 14325^2 + 2429^2 .

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

It is not an unprimeable number, because it can be changed into a prime (211105663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 114571 + ... + 116398.

Almost surely, 2^211105666 is an apocalyptic number.

211105666 is a deficient number, since it is larger than the sum of its proper divisors (106247114).

211105666 is a wasteful number, since it uses less digits than its factorization.

211105666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231428.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 211105666 is about 14529.4757648031. The cubic root of 211105666 is about 595.4335432153.

Adding to 211105666 its reverse (666501112), we get a palindrome (877606778).

The spelling of 211105666 in words is "two hundred eleven million, one hundred five thousand, six hundred sixty-six".