2112112021 has 4 divisors (see below), whose sum is σ = 2184943500. Its totient is φ = 2039280544.

The previous prime is 2112111979. The next prime is 2112112049. The reversal of 2112112021 is 1202112112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1695380625 + 416731396 = 41175^2 + 20414^2 .

It is a cyclic number.

It is not a de Polignac number, because 2112112021 - 2⁷ = 2112111893 is a prime.

It is a super-2 number, since 2×2112112021² = 8922034378505408882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2112111992 and 2112112010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2112412021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36415696 + ... + 36415753.

It is an arithmetic number, because the mean of its divisors is an integer number (546235875).

Almost surely, 2^2112112021 is an apocalyptic number.

It is an amenable number.

2112112021 is a deficient number, since it is larger than the sum of its proper divisors (72831479).

2112112021 is an equidigital number, since it uses as much as digits as its factorization.

2112112021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72831478.

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 2112112021 is about 45957.7199282123. The cubic root of 2112112021 is about 1283.0364153854.

Adding to 2112112021 its reverse (1202112112), we get a palindrome (3314224133).

Subtracting from 2112112021 its reverse (1202112112), we obtain a palindrome (909999909).

The spelling of 2112112021 in words is "two billion, one hundred twelve million, one hundred twelve thousand, twenty-one".