21333221011 has 4 divisors (see below), whose sum is σ = 21336417000. Its totient is φ = 21330025024.

The previous prime is 21333220991. The next prime is 21333221029. The reversal of 21333221011 is 11012233312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21333221011 - 2²⁷ = 21199003283 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21333221011.

It is not an unprimeable number, because it can be changed into a prime (21333221911) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1587961 + ... + 1601338.

It is an arithmetic number, because the mean of its divisors is an integer number (5334104250).

Almost surely, 2^21333221011 is an apocalyptic number.

21333221011 is a deficient number, since it is larger than the sum of its proper divisors (3195989).

21333221011 is an equidigital number, since it uses as much as digits as its factorization.

21333221011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3195988.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21333221011 its reverse (11012233312), we get a palindrome (32345454323).

The spelling of 21333221011 in words is "twenty-one billion, three hundred thirty-three million, two hundred twenty-one thousand, eleven".