21212012220111 has 12 divisors (see below), whose sum is σ = 30667503552192. Its totient is φ = 14128450551456.

The previous prime is 21212012220083. The next prime is 21212012220247. The reversal of 21212012220111 is 11102221021212.

21212012220111 is a `hidden beast` number, since 212 + 120 + 1 + 2 + 220 + 111 = 666.

It is not a de Polignac number, because 21212012220111 - 2¹¹ = 21212012218063 is a prime.

It is a super-2 number, since 2×21212012220111² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212012220611) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1074233631 + ... + 1074253376.

It is an arithmetic number, because the mean of its divisors is an integer number (2555625296016).

Almost surely, 2^{21212012220111} is an apocalyptic number.

21212012220111 is a deficient number, since it is larger than the sum of its proper divisors (9455491332081).

21212012220111 is a wasteful number, since it uses less digits than its factorization.

21212012220111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2148488110 (or 2148488107 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21212012220111 its reverse (11102221021212), we get a palindrome (32314233241323).

The spelling of 21212012220111 in words is "twenty-one trillion, two hundred twelve billion, twelve million, two hundred twenty thousand, one hundred eleven".