21222121202112 has 56 divisors (see below), whose sum is σ = 56560051193616. Its totient is φ = 7022405060608.

The previous prime is 21222121202111. The next prime is 21222121202143. The reversal of 21222121202112 is 21120212122212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222121202111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 403374723 + ... + 403427330.

Almost surely, 2^{21222121202112} is an apocalyptic number.

It is an amenable number.

21222121202112 is an abundant number, since it is smaller than the sum of its proper divisors (35337929991504).

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

21222121202112 is a wasteful number, since it uses less digits than its factorization.

21222121202112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 806802205 (or 806802195 counting only the distinct ones).

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

Adding to 21222121202112 its reverse (21120212122212), we get a palindrome (42342333324324).

The spelling of 21222121202112 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred twenty-one million, two hundred two thousand, one hundred twelve".