21710660566 has 8 divisors (see below), whose sum is σ = 37218275280. Its totient is φ = 9304568808.

The previous prime is 21710660563. The next prime is 21710660567. The reversal of 21710660566 is 66506601712.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21710660563) 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 3 ways as a sum of consecutive naturals, for example, 775380721 + ... + 775380748.

It is an arithmetic number, because the mean of its divisors is an integer number (4652284410).

Almost surely, 2^21710660566 is an apocalyptic number.

21710660566 is a deficient number, since it is larger than the sum of its proper divisors (15507614714).

21710660566 is a wasteful number, since it uses less digits than its factorization.

21710660566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1550761478.

The product of its (nonzero) digits is 90720, while the sum is 40.

It can be divided in two parts, 21710 and 660566, that added together give a square (682276 = 826²).

The spelling of 21710660566 in words is "twenty-one billion, seven hundred ten million, six hundred sixty thousand, five hundred sixty-six".