21201221012212 has 48 divisors (see below), whose sum is σ = 38743913779200. Its totient is φ = 10138882557440.

The previous prime is 21201221012071. The next prime is 21201221012233. The reversal of 21201221012212 is 21221012210212.

It is a self number, because there is not a number n which added to its sum of digits gives 21201221012212.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3293388 + ... + 7297180.

It is an arithmetic number, because the mean of its divisors is an integer number (807164870400).

Almost surely, 2^{21201221012212} is an apocalyptic number.

It is an amenable number.

21201221012212 is a deficient number, since it is larger than the sum of its proper divisors (17542692766988).

21201221012212 is a wasteful number, since it uses less digits than its factorization.

21201221012212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4004256 (or 4004254 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21201221012212 its reverse (21221012210212), we get a palindrome (42422233222424).

The spelling of 21201221012212 in words is "twenty-one trillion, two hundred one billion, two hundred twenty-one million, twelve thousand, two hundred twelve".