21212211222012 has 24 divisors (see below), whose sum is σ = 49603464037456. Its totient is φ = 7055264999808.

The previous prime is 21212211221989. The next prime is 21212211222043. The reversal of 21212211222012 is 21022211221212.

It is a self number, because there is not a number n which added to its sum of digits gives 21212211222012.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1934003563 + ... + 1934014530.

Almost surely, 2^{21212211222012} is an apocalyptic number.

It is an amenable number.

21212211222012 is an abundant number, since it is smaller than the sum of its proper divisors (28391252815444).

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

21212211222012 is a wasteful number, since it uses less digits than its factorization.

21212211222012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3868018557 (or 3868018555 counting only the distinct ones).

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

Adding to 21212211222012 its reverse (21022211221212), we get a palindrome (42234422443224).

The spelling of 21212211222012 in words is "twenty-one trillion, two hundred twelve billion, two hundred eleven million, two hundred twenty-two thousand, twelve".