21212110122211 has 4 divisors (see below), whose sum is σ = 21214667963632. Its totient is φ = 21209552280792.

The previous prime is 21212110122173. The next prime is 21212110122223. The reversal of 21212110122211 is 11222101121212.

It is a happy number.

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 21212110122211 - 2³¹ = 21209962638563 is a prime.

It is a super-3 number, since 3×21212110122211³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21212110122251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1278908271 + ... + 1278924856.

It is an arithmetic number, because the mean of its divisors is an integer number (5303666990908).

Almost surely, 2^{21212110122211} is an apocalyptic number.

21212110122211 is a deficient number, since it is larger than the sum of its proper divisors (2557841421).

21212110122211 is an equidigital number, since it uses as much as digits as its factorization.

21212110122211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2557841420.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21212110122211 its reverse (11222101121212), we get a palindrome (32434211243423).

Subtracting from 21212110122211 its reverse (11222101121212), we obtain a palindrome (9990009000999).

The spelling of 21212110122211 in words is "twenty-one trillion, two hundred twelve billion, one hundred ten million, one hundred twenty-two thousand, two hundred eleven".