21111212122212 has 24 divisors (see below), whose sum is σ = 50848510918912. Its totient is φ = 6810068426400.

The previous prime is 21111212122201. The next prime is 21111212122241. The reversal of 21111212122212 is 21222121211112.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28375284739 + ... + 28375285482.

Almost surely, 2^{21111212122212} is an apocalyptic number.

It is an amenable number.

21111212122212 is an abundant number, since it is smaller than the sum of its proper divisors (29737298796700).

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

21111212122212 is a wasteful number, since it uses less digits than its factorization.

21111212122212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56750570259 (or 56750570257 counting only the distinct ones).

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

Adding to 21111212122212 its reverse (21222121211112), we get a palindrome (42333333333324).

The spelling of 21111212122212 in words is "twenty-one trillion, one hundred eleven billion, two hundred twelve million, one hundred twenty-two thousand, two hundred twelve".