21122221121212 has 24 divisors (see below), whose sum is σ = 38231233729920. Its totient is φ = 10200350114880.

The previous prime is 21122221121201. The next prime is 21122221121237. The reversal of 21122221121212 is 21212112222112.

It is a super-2 number, since 2×21122221121212² (a number of 27 digits) contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

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, 167265463 + ... + 167391694.

It is an arithmetic number, because the mean of its divisors is an integer number (1592968072080).

Almost surely, 2^{21122221121212} is an apocalyptic number.

It is an amenable number.

21122221121212 is a deficient number, since it is larger than the sum of its proper divisors (17109012608708).

21122221121212 is a wasteful number, since it uses less digits than its factorization.

21122221121212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334657701 (or 334657699 counting only the distinct ones).

The product of its digits is 256, while the sum is 22.

Adding to 21122221121212 its reverse (21212112222112), we get a palindrome (42334333343324).

The spelling of 21122221121212 in words is "twenty-one trillion, one hundred twenty-two billion, two hundred twenty-one million, one hundred twenty-one thousand, two hundred twelve".