11111121221009 has 2 divisors, whose sum is σ = 11111121221010. Its totient is φ = 11111121221008.

The previous prime is 11111121220967. The next prime is 11111121221021. The reversal of 11111121221009 is 90012212111111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11072755380625 + 38365840384 = 3327575^2 + 195872^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11111121221009 is a prime.

It is not a weakly prime, because it can be changed into another prime (11111121221089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5555560610504 + 5555560610505.

It is an arithmetic number, because the mean of its divisors is an integer number (5555560610505).

Almost surely, 2^{11111121221009} is an apocalyptic number.

It is an amenable number.

11111121221009 is a deficient number, since it is larger than the sum of its proper divisors (1).

11111121221009 is an equidigital number, since it uses as much as digits as its factorization.

11111121221009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 23.

The spelling of 11111121221009 in words is "eleven trillion, one hundred eleven billion, one hundred twenty-one million, two hundred twenty-one thousand, nine".