21224115211 has 4 divisors (see below), whose sum is σ = 22856739472. Its totient is φ = 19591490952.

The previous prime is 21224115169. The next prime is 21224115221. The reversal of 21224115211 is 11251142212.

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 21224115211 - 2⁹ = 21224114699 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21224115221) 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, 816312111 + ... + 816312136.

It is an arithmetic number, because the mean of its divisors is an integer number (5714184868).

Almost surely, 2^21224115211 is an apocalyptic number.

21224115211 is a deficient number, since it is larger than the sum of its proper divisors (1632624261).

21224115211 is a wasteful number, since it uses less digits than its factorization.

21224115211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1632624260.

The product of its digits is 320, while the sum is 22.

Adding to 21224115211 its reverse (11251142212), we get a palindrome (32475257423).

The spelling of 21224115211 in words is "twenty-one billion, two hundred twenty-four million, one hundred fifteen thousand, two hundred eleven".