21433440211 has 4 divisors (see below), whose sum is σ = 21461168592. Its totient is φ = 21405711832.

The previous prime is 21433440191. The next prime is 21433440227. The reversal of 21433440211 is 11204433412.

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 21433440211 - 2¹⁹ = 21432915923 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21433440811) 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, 13863031 + ... + 13864576.

It is an arithmetic number, because the mean of its divisors is an integer number (5365292148).

Almost surely, 2^21433440211 is an apocalyptic number.

21433440211 is a deficient number, since it is larger than the sum of its proper divisors (27728381).

21433440211 is an equidigital number, since it uses as much as digits as its factorization.

21433440211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27728380.

The product of its (nonzero) digits is 2304, while the sum is 25.

Adding to 21433440211 its reverse (11204433412), we get a palindrome (32637873623).

The spelling of 21433440211 in words is "twenty-one billion, four hundred thirty-three million, four hundred forty thousand, two hundred eleven".