1121999209 has 2 divisors, whose sum is σ = 1121999210. Its totient is φ = 1121999208.

The previous prime is 1121999189. The next prime is 1121999227. The reversal of 1121999209 is 9029991211.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 716097600 + 405901609 = 26760^2 + 20147^2 .

It is a cyclic number.

It is not a de Polignac number, because 1121999209 - 2²¹ = 1119902057 is a prime.

It is not a weakly prime, because it can be changed into another prime (1121991209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 560999604 + 560999605.

It is an arithmetic number, because the mean of its divisors is an integer number (560999605).

Almost surely, 2^1121999209 is an apocalyptic number.

It is an amenable number.

1121999209 is a deficient number, since it is larger than the sum of its proper divisors (1).

1121999209 is an equidigital number, since it uses as much as digits as its factorization.

1121999209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26244, while the sum is 43.

The square root of 1121999209 is about 33496.2566416010. The cubic root of 1121999209 is about 1039.1163626563.

The spelling of 1121999209 in words is "one billion, one hundred twenty-one million, nine hundred ninety-nine thousand, two hundred nine".