1211002211209 has 12 divisors (see below), whose sum is σ = 1410213953988. Its totient is φ = 1036898772000.

The previous prime is 1211002211207. The next prime is 1211002211267. The reversal of 1211002211209 is 9021122001121.

It can be written as a sum of positive squares in 2 ways, for example, as 304231671184 + 906770540025 = 551572^2 + 952245^2 .

It is not a de Polignac number, because 1211002211209 - 2¹ = 1211002211207 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1211002211209.

It is not an unprimeable number, because it can be changed into a prime (1211002211207) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13085842 + ... + 13178059.

It is an arithmetic number, because the mean of its divisors is an integer number (117517829499).

Almost surely, 2^{1211002211209} is an apocalyptic number.

It is an amenable number.

1211002211209 is a deficient number, since it is larger than the sum of its proper divisors (199211742779).

1211002211209 is an equidigital number, since it uses as much as digits as its factorization.

1211002211209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26264856 (or 26264849 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 22.

The spelling of 1211002211209 in words is "one trillion, two hundred eleven billion, two million, two hundred eleven thousand, two hundred nine".