11111220611 has 2 divisors, whose sum is σ = 11111220612. Its totient is φ = 11111220610.

The previous prime is 11111220557. The next prime is 11111220623. The reversal of 11111220611 is 11602211111.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11111220611 is a prime.

It is a super-2 number, since 2×11111220611² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11111220611.

It is not a weakly prime, because it can be changed into another prime (11111220671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5555610305 + 5555610306.

It is an arithmetic number, because the mean of its divisors is an integer number (5555610306).

Almost surely, 2^11111220611 is an apocalyptic number.

11111220611 is a deficient number, since it is larger than the sum of its proper divisors (1).

11111220611 is an equidigital number, since it uses as much as digits as its factorization.

11111220611 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 17.

Adding to 11111220611 its reverse (11602211111), we get a palindrome (22713431722).

The spelling of 11111220611 in words is "eleven billion, one hundred eleven million, two hundred twenty thousand, six hundred eleven".