21222102121212 has 48 divisors (see below), whose sum is σ = 50153665226112. Its totient is φ = 6983390809920.

The previous prime is 21222102121169. The next prime is 21222102121261. The reversal of 21222102121212 is 21212120122212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6966423 + ... + 9538094.

It is an arithmetic number, because the mean of its divisors is an integer number (1044868025544).

Almost surely, 2^{21222102121212} is an apocalyptic number.

It is an amenable number.

21222102121212 is an abundant number, since it is smaller than the sum of its proper divisors (28931563104900).

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

21222102121212 is a wasteful number, since it uses less digits than its factorization.

21222102121212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16505898 (or 16505896 counting only the distinct ones).

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

Adding to 21222102121212 its reverse (21212120122212), we get a palindrome (42434222243424).

The spelling of 21222102121212 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred two million, one hundred twenty-one thousand, two hundred twelve".