2212120021 has 4 divisors (see below), whose sum is σ = 2212291692. Its totient is φ = 2211948352.

The previous prime is 2212119983. The next prime is 2212120069. The reversal of 2212120021 is 1200212122.

It is a happy number.

2212120021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1200212122 = 2 ⋅600106061.

It can be written as a sum of positive squares in 2 ways, for example, as 1217032996 + 995087025 = 34886^2 + 31545^2 .

It is a cyclic number.

It is not a de Polignac number, because 2212120021 - 2⁷ = 2212119893 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2212119983 and 2212120010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2212120081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64786 + ... + 92851.

It is an arithmetic number, because the mean of its divisors is an integer number (553072923).

Almost surely, 2^2212120021 is an apocalyptic number.

It is an amenable number.

2212120021 is a deficient number, since it is larger than the sum of its proper divisors (171671).

2212120021 is a wasteful number, since it uses less digits than its factorization.

2212120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171670.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 2212120021 is about 47033.1800009313. The cubic root of 2212120021 is about 1302.9754372923.

Adding to 2212120021 its reverse (1200212122), we get a palindrome (3412332143).

The spelling of 2212120021 in words is "two billion, two hundred twelve million, one hundred twenty thousand, twenty-one".