21200001211 has 4 divisors (see below), whose sum is σ = 21219983424. Its totient is φ = 21180019000.

The previous prime is 21200001197. The next prime is 21200001223. The reversal of 21200001211 is 11210000212.

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 21200001211 - 2¹⁵ = 21199968443 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21200001281) 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, 9989515 + ... + 9991636.

It is an arithmetic number, because the mean of its divisors is an integer number (5304995856).

Almost surely, 2^21200001211 is an apocalyptic number.

21200001211 is a deficient number, since it is larger than the sum of its proper divisors (19982213).

21200001211 is a wasteful number, since it uses less digits than its factorization.

21200001211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19982212.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21200001211 its reverse (11210000212), we get a palindrome (32410001423).

Subtracting from 21200001211 its reverse (11210000212), we obtain a palindrome (9990000999).

It can be divided in two parts, 21200001 and 211, that added together give a palindrome (21200212).

The spelling of 21200001211 in words is "twenty-one billion, two hundred million, one thousand, two hundred eleven".