1220211011209 has 4 divisors (see below), whose sum is σ = 1233921247380. Its totient is φ = 1206500775040.

The previous prime is 1220211011191. The next prime is 1220211011221. The reversal of 1220211011209 is 9021101120221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 546375245584 + 673835765625 = 739172^2 + 820875^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220211011209 - 2⁵ = 1220211011177 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 1220211011209.

It is not an unprimeable number, because it can be changed into a prime (1220211011009) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6855117952 + ... + 6855118129.

It is an arithmetic number, because the mean of its divisors is an integer number (308480311845).

Almost surely, 2^{1220211011209} is an apocalyptic number.

It is an amenable number.

1220211011209 is a deficient number, since it is larger than the sum of its proper divisors (13710236171).

1220211011209 is an equidigital number, since it uses as much as digits as its factorization.

1220211011209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13710236170.

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

The spelling of 1220211011209 in words is "one trillion, two hundred twenty billion, two hundred eleven million, eleven thousand, two hundred nine".