21706811066 has 8 divisors (see below), whose sum is σ = 32560843764. Its totient is φ = 10853196480.

The previous prime is 21706811057. The next prime is 21706811099. The reversal of 21706811066 is 66011860712.

It can be written as a sum of positive squares in 2 ways, for example, as 19190283841 + 2516527225 = 138529^2 + 50165^2 .

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

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 135506 + ... + 248546.

Almost surely, 2^21706811066 is an apocalyptic number.

21706811066 is a deficient number, since it is larger than the sum of its proper divisors (10854032698).

21706811066 is a wasteful number, since it uses less digits than its factorization.

21706811066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209056.

The product of its (nonzero) digits is 24192, while the sum is 38.

The spelling of 21706811066 in words is "twenty-one billion, seven hundred six million, eight hundred eleven thousand, sixty-six".