2121202221 has 8 divisors (see below), whose sum is σ = 2835655680. Its totient is φ = 1410441792.

The previous prime is 2121202211. The next prime is 2121202231. The reversal of 2121202221 is 1222021212.

It is an interprime number because it is at equal distance from previous prime (2121202211) and next prime (2121202231).

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

It is not a de Polignac number, because 2121202221 - 2³⁰ = 1047460397 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2121202221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121202211) 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, 921916 + ... + 924213.

It is an arithmetic number, because the mean of its divisors is an integer number (354456960).

Almost surely, 2^2121202221 is an apocalyptic number.

It is an amenable number.

2121202221 is a deficient number, since it is larger than the sum of its proper divisors (714453459).

2121202221 is a wasteful number, since it uses less digits than its factorization.

2121202221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1846515.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 2121202221 is about 46056.5111683462. The cubic root of 2121202221 is about 1284.8744437676.

Adding to 2121202221 its reverse (1222021212), we get a palindrome (3343223433).

The spelling of 2121202221 in words is "two billion, one hundred twenty-one million, two hundred two thousand, two hundred twenty-one".