21121120212 has 24 divisors (see below), whose sum is σ = 52181591616. Its totient is φ = 6626233728.

The previous prime is 21121120211. The next prime is 21121120217. The reversal of 21121120212 is 21202112112.

It is a super-2 number, since 2×21121120212² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21121120191 and 21121120200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121120211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51767248 + ... + 51767655.

It is an arithmetic number, because the mean of its divisors is an integer number (2174232984).

Almost surely, 2^21121120212 is an apocalyptic number.

It is an amenable number.

21121120212 is an abundant number, since it is smaller than the sum of its proper divisors (31060471404).

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

21121120212 is a wasteful number, since it uses less digits than its factorization.

21121120212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103534927 (or 103534925 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21121120212 its reverse (21202112112), we get a palindrome (42323232324).

The spelling of 21121120212 in words is "twenty-one billion, one hundred twenty-one million, one hundred twenty thousand, two hundred twelve".