21221112212112 has 40 divisors (see below), whose sum is σ = 54881383616640. Its totient is φ = 7065939287680.

The previous prime is 21221112212107. The next prime is 21221112212119. The reversal of 21221112212112 is 21121221112212.

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

It is not an unprimeable number, because it can be changed into a prime (21221112212119) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 242605287 + ... + 242692742.

It is an arithmetic number, because the mean of its divisors is an integer number (1372034590416).

Almost surely, 2^{21221112212112} is an apocalyptic number.

It is an amenable number.

21221112212112 is an abundant number, since it is smaller than the sum of its proper divisors (33660271404528).

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

21221112212112 is a wasteful number, since it uses less digits than its factorization.

21221112212112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485298951 (or 485298945 counting only the distinct ones).

The product of its digits is 128, while the sum is 21.

Adding to 21221112212112 its reverse (21121221112212), we get a palindrome (42342333324324).

The spelling of 21221112212112 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twelve million, two hundred twelve thousand, one hundred twelve".