11211122009 has 2 divisors, whose sum is σ = 11211122010. Its totient is φ = 11211122008.

The previous prime is 11211121973. The next prime is 11211122033. The reversal of 11211122009 is 90022111211.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6455640409 + 4755481600 = 80347^2 + 68960^2 .

It is an emirp because it is prime and its reverse (90022111211) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11211122009 is a prime.

It is not a weakly prime, because it can be changed into another prime (11211122089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5605561004 + 5605561005.

It is an arithmetic number, because the mean of its divisors is an integer number (5605561005).

Almost surely, 2^11211122009 is an apocalyptic number.

It is an amenable number.

11211122009 is a deficient number, since it is larger than the sum of its proper divisors (1).

11211122009 is an equidigital number, since it uses as much as digits as its factorization.

11211122009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 20.

The spelling of 11211122009 in words is "eleven billion, two hundred eleven million, one hundred twenty-two thousand, nine".