21302661866 has 8 divisors (see below), whose sum is σ = 32817614340. Its totient is φ = 10363457088.

The previous prime is 21302661833. The next prime is 21302661907. The reversal of 21302661866 is 66816620312.

It can be written as a sum of positive squares in 2 ways, for example, as 20672400841 + 630261025 = 143779^2 + 25105^2 .

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

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, 143936831 + ... + 143936978.

Almost surely, 2^21302661866 is an apocalyptic number.

21302661866 is a deficient number, since it is larger than the sum of its proper divisors (11514952474).

21302661866 is a wasteful number, since it uses less digits than its factorization.

21302661866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287873848.

The product of its (nonzero) digits is 124416, while the sum is 41.

The spelling of 21302661866 in words is "twenty-one billion, three hundred two million, six hundred sixty-one thousand, eight hundred sixty-six".