21122211220211 has 4 divisors (see below), whose sum is σ = 21122220654000. Its totient is φ = 21122201786424.

The previous prime is 21122211220207. The next prime is 21122211220267. The reversal of 21122211220211 is 11202211222112.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21122211220211 - 2² = 21122211220207 is a prime.

It is a super-2 number, since 2×21122211220211² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21122211220291) 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, 766130 + ... + 6544568.

It is an arithmetic number, because the mean of its divisors is an integer number (5280555163500).

Almost surely, 2^{21122211220211} is an apocalyptic number.

21122211220211 is a deficient number, since it is larger than the sum of its proper divisors (9433789).

21122211220211 is an equidigital number, since it uses as much as digits as its factorization.

21122211220211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9433788.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 21122211220211 its reverse (11202211222112), we get a palindrome (32324422442323).

The spelling of 21122211220211 in words is "twenty-one trillion, one hundred twenty-two billion, two hundred eleven million, two hundred twenty thousand, two hundred eleven".