211566406444 has 24 divisors (see below), whose sum is σ = 392035146048. Its totient is φ = 99556842240.

The previous prime is 211566406409. The next prime is 211566406507. The reversal of 211566406444 is 444604665112.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 211566406444.

It is an unprimeable number.

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, 2574349 + ... + 2655259.

It is an arithmetic number, because the mean of its divisors is an integer number (16334797752).

Almost surely, 2^211566406444 is an apocalyptic number.

It is an amenable number.

211566406444 is a deficient number, since it is larger than the sum of its proper divisors (180468739604).

211566406444 is a wasteful number, since it uses less digits than its factorization.

211566406444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119385 (or 119383 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 43.

The spelling of 211566406444 in words is "two hundred eleven billion, five hundred sixty-six million, four hundred six thousand, four hundred forty-four".