21212000012 has 24 divisors (see below), whose sum is σ = 42428650656. Its totient is φ = 9089860608.

The previous prime is 21211999979. The next prime is 21212000021. The reversal of 21212000012 is 21000021212.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21211999957 and 21212000002.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 255818 + ... + 328430.

It is an arithmetic number, because the mean of its divisors is an integer number (1767860444).

Almost surely, 2^21212000012 is an apocalyptic number.

It is an amenable number.

21212000012 is an abundant number, since it is smaller than the sum of its proper divisors (21216650644).

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

21212000012 is a wasteful number, since it uses less digits than its factorization.

21212000012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83057 (or 83055 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21212000012 its reverse (21000021212), we get a palindrome (42212021224).

The spelling of 21212000012 in words is "twenty-one billion, two hundred twelve million, twelve", and thus it is an aban number.