21212110022112 has 72 divisors (see below), whose sum is σ = 62402004723240. Its totient is φ = 6826885981440.

The previous prime is 21212110022009. The next prime is 21212110022177. The reversal of 21212110022112 is 21122001121212.

21212110022112 is a `hidden beast` number, since 212 + 121 + 100 + 221 + 12 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-3 number, since 3×21212110022112³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1269873714 + ... + 1269890417.

It is an arithmetic number, because the mean of its divisors is an integer number (866694510045).

Almost surely, 2^{21212110022112} is an apocalyptic number.

It is an amenable number.

21212110022112 is an abundant number, since it is smaller than the sum of its proper divisors (41189894701128).

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

21212110022112 is a wasteful number, since it uses less digits than its factorization.

21212110022112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2539764176 (or 2539764165 counting only the distinct ones).

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

Adding to 21212110022112 its reverse (21122001121212), we get a palindrome (42334111143324).

The spelling of 21212110022112 in words is "twenty-one trillion, two hundred twelve billion, one hundred ten million, twenty-two thousand, one hundred twelve".