1211121101209 has 16 divisors (see below), whose sum is σ = 1283125605120. Its totient is φ = 1140768256320.

The previous prime is 1211121101119. The next prime is 1211121101213. The reversal of 1211121101209 is 9021011211121.

It is a happy number.

It is not a de Polignac number, because 1211121101209 - 2¹¹ = 1211121099161 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1211121101209.

It is not an unprimeable number, because it can be changed into a prime (1211121101219) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 906439 + ... + 1801075.

It is an arithmetic number, because the mean of its divisors is an integer number (80195350320).

Almost surely, 2^{1211121101209} is an apocalyptic number.

It is an amenable number.

1211121101209 is a deficient number, since it is larger than the sum of its proper divisors (72004503911).

1211121101209 is an equidigital number, since it uses as much as digits as its factorization.

1211121101209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 895560.

The product of its (nonzero) digits is 72, while the sum is 22.

The spelling of 1211121101209 in words is "one trillion, two hundred eleven billion, one hundred twenty-one million, one hundred one thousand, two hundred nine".