1211020112209 has 2 divisors, whose sum is σ = 1211020112210. Its totient is φ = 1211020112208.

The previous prime is 1211020112153. The next prime is 1211020112251. The reversal of 1211020112209 is 9022110201121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 684843967809 + 526176144400 = 827553^2 + 725380^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211020112209 - 2²⁵ = 1210986557777 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1211020112209.

It is not a weakly prime, because it can be changed into another prime (1211020112299) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605510056104 + 605510056105.

It is an arithmetic number, because the mean of its divisors is an integer number (605510056105).

Almost surely, 2^{1211020112209} is an apocalyptic number.

It is an amenable number.

1211020112209 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211020112209 is an equidigital number, since it uses as much as digits as its factorization.

1211020112209 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 22.

The spelling of 1211020112209 in words is "one trillion, two hundred eleven billion, twenty million, one hundred twelve thousand, two hundred nine".