11221121111 has 2 divisors, whose sum is σ = 11221121112. Its totient is φ = 11221121110.

The previous prime is 11221121101. The next prime is 11221121123. The reversal of 11221121111 is 11112112211.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11221121111 - 2⁶ = 11221121047 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11221121101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5610560555 + 5610560556.

It is an arithmetic number, because the mean of its divisors is an integer number (5610560556).

Almost surely, 2^11221121111 is an apocalyptic number.

11221121111 is a deficient number, since it is larger than the sum of its proper divisors (1).

11221121111 is an equidigital number, since it uses as much as digits as its factorization.

11221121111 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8, while the sum is 14.

Adding to 11221121111 its reverse (11112112211), we get a palindrome (22333233322).

It can be divided in two parts, 11 and 221121111, that added together give a palindrome (221121122).

The spelling of 11221121111 in words is "eleven billion, two hundred twenty-one million, one hundred twenty-one thousand, one hundred eleven".