21212122220112 has 20 divisors (see below), whose sum is σ = 54797982402080. Its totient is φ = 7070707406688.

The previous prime is 21212122220101. The next prime is 21212122220123. The reversal of 21212122220112 is 21102222121212.

It is an interprime number because it is at equal distance from previous prime (21212122220101) and next prime (21212122220123).

It is a super-3 number, since 3×21212122220112³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 220959606412 + ... + 220959606507.

It is an arithmetic number, because the mean of its divisors is an integer number (2739899120104).

Almost surely, 2^{21212122220112} is an apocalyptic number.

It is an amenable number.

21212122220112 is an abundant number, since it is smaller than the sum of its proper divisors (33585860181968).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21212122220112 is a wasteful number, since it uses less digits than its factorization.

21212122220112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 441919212930 (or 441919212924 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 21212122220112 its reverse (21102222121212), we get a palindrome (42314344341324).

The spelling of 21212122220112 in words is "twenty-one trillion, two hundred twelve billion, one hundred twenty-two million, two hundred twenty thousand, one hundred twelve".