2101220100209 has 2 divisors, whose sum is σ = 2101220100210. Its totient is φ = 2101220100208.

The previous prime is 2101220100181. The next prime is 2101220100251. The reversal of 2101220100209 is 9020010221012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2099899504609 + 1320595600 = 1449103^2 + 36340^2 .

It is a cyclic number.

It is not a de Polignac number, because 2101220100209 - 2¹⁶ = 2101220034673 is a prime.

It is a super-3 number, since 3×2101220100209³ (a number of 38 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (2101220102209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050610050104 + 1050610050105.

It is an arithmetic number, because the mean of its divisors is an integer number (1050610050105).

Almost surely, 2^{2101220100209} is an apocalyptic number.

It is an amenable number.

2101220100209 is a deficient number, since it is larger than the sum of its proper divisors (1).

2101220100209 is an equidigital number, since it uses as much as digits as its factorization.

2101220100209 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 20.

The spelling of 2101220100209 in words is "two trillion, one hundred one billion, two hundred twenty million, one hundred thousand, two hundred nine".