21803336666 has 8 divisors (see below), whose sum is σ = 32994430164. Its totient is φ = 10805193280.

The previous prime is 21803336651. The next prime is 21803336693. The reversal of 21803336666 is 66663330812.

It can be written as a sum of positive squares in 2 ways, for example, as 21353684641 + 449652025 = 146129^2 + 21205^2 .

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

It is a Curzon number.

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, 48237245 + ... + 48237696.

Almost surely, 2^21803336666 is an apocalyptic number.

21803336666 is a deficient number, since it is larger than the sum of its proper divisors (11191093498).

21803336666 is a wasteful number, since it uses less digits than its factorization.

21803336666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96475056.

The product of its (nonzero) digits is 559872, while the sum is 44.

The spelling of 21803336666 in words is "twenty-one billion, eight hundred three million, three hundred thirty-six thousand, six hundred sixty-six".