21212012112 has 40 divisors (see below), whose sum is σ = 54836383104. Its totient is φ = 7065679104.

The previous prime is 21212012069. The next prime is 21212012141. The reversal of 21212012112 is 21121021212.

It is a junction number, because it is equal to n+sod(n) for n = 21212012091 and 21212012100.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86973 + ... + 223580.

Almost surely, 2^21212012112 is an apocalyptic number.

It is an amenable number.

21212012112 is an abundant number, since it is smaller than the sum of its proper divisors (33624370992).

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

21212012112 is a wasteful number, since it uses less digits than its factorization.

21212012112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 311987 (or 311981 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21212012112 its reverse (21121021212), we get a palindrome (42333033324).

The spelling of 21212012112 in words is "twenty-one billion, two hundred twelve million, twelve thousand, one hundred twelve".