2120211221 has 8 divisors (see below), whose sum is σ = 2156019000. Its totient is φ = 2084437440.

The previous prime is 2120211169. The next prime is 2120211239. The reversal of 2120211221 is 1221120212.

It can be written as a sum of positive squares in 4 ways, for example, as 35832196 + 2084379025 = 5986^2 + 45655^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2120211221 - 2⁶ = 2120211157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2120211196 and 2120211205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2120211281) 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, 138455 + ... + 153003.

It is an arithmetic number, because the mean of its divisors is an integer number (269502375).

Almost surely, 2^2120211221 is an apocalyptic number.

It is an amenable number.

2120211221 is a deficient number, since it is larger than the sum of its proper divisors (35807779).

2120211221 is a wasteful number, since it uses less digits than its factorization.

2120211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16999.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 2120211221 is about 46045.7513892433. The cubic root of 2120211221 is about 1284.6743200037.

Adding to 2120211221 its reverse (1221120212), we get a palindrome (3341331433).

It can be divided in two parts, 21202 and 11221, that added together give a palindrome (32423).

The spelling of 2120211221 in words is "two billion, one hundred twenty million, two hundred eleven thousand, two hundred twenty-one".