2121200209 has 2 divisors, whose sum is σ = 2121200210. Its totient is φ = 2121200208.

The previous prime is 2121200183. The next prime is 2121200293. The reversal of 2121200209 is 9020021212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1467273025 + 653927184 = 38305^2 + 25572^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121200209 - 2⁹ = 2121199697 is a prime.

It is not a weakly prime, because it can be changed into another prime (2121200909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060600104 + 1060600105.

It is an arithmetic number, because the mean of its divisors is an integer number (1060600105).

Almost surely, 2^2121200209 is an apocalyptic number.

It is an amenable number.

2121200209 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121200209 is an equidigital number, since it uses as much as digits as its factorization.

2121200209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 2121200209 is about 46056.4893256097. The cubic root of 2121200209 is about 1284.8740375250.

The spelling of 2121200209 in words is "two billion, one hundred twenty-one million, two hundred thousand, two hundred nine".