21221102212 has 12 divisors (see below), whose sum is σ = 37138823820. Its totient is φ = 10610009696.

The previous prime is 21221102209. The next prime is 21221102249. The reversal of 21221102212 is 21220112212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 4813029376 + 16408072836 = 69376^2 + 128094^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39643 + ... + 209794.

It is an arithmetic number, because the mean of its divisors is an integer number (3094901985).

Almost surely, 2^21221102212 is an apocalyptic number.

It is an amenable number.

21221102212 is a deficient number, since it is larger than the sum of its proper divisors (15917721608).

21221102212 is a wasteful number, since it uses less digits than its factorization.

21221102212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270710 (or 270708 counting only the distinct ones).

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

Adding to 21221102212 its reverse (21220112212), we get a palindrome (42441214424).

The spelling of 21221102212 in words is "twenty-one billion, two hundred twenty-one million, one hundred two thousand, two hundred twelve".