21122012212 has 24 divisors (see below), whose sum is σ = 42270500160. Its totient is φ = 9046617600.

The previous prime is 21122012183. The next prime is 21122012227. The reversal of 21122012212 is 21221022112.

It is a happy number.

It is a super-2 number, since 2×21122012212² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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, 190762 + ... + 280417.

It is an arithmetic number, because the mean of its divisors is an integer number (1761270840).

Almost surely, 2^21122012212 is an apocalyptic number.

It is an amenable number.

21122012212 is an abundant number, since it is smaller than the sum of its proper divisors (21148487948).

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

21122012212 is a wasteful number, since it uses less digits than its factorization.

21122012212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472791 (or 472789 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21122012212 its reverse (21221022112), we get a palindrome (42343034324).

The spelling of 21122012212 in words is "twenty-one billion, one hundred twenty-two million, twelve thousand, two hundred twelve".