11111221011 has 64 divisors (see below), whose sum is σ = 16693433856. Its totient is φ = 6517555200.

The previous prime is 11111221007. The next prime is 11111221013. The reversal of 11111221011 is 11012211111.

11111221011 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 11111221011 - 2² = 11111221007 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11111221013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 43234195 + ... + 43234451.

It is an arithmetic number, because the mean of its divisors is an integer number (260834904).

Almost surely, 2^11111221011 is an apocalyptic number.

11111221011 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11111221011 is a deficient number, since it is larger than the sum of its proper divisors (5582212845).

11111221011 is a wasteful number, since it uses less digits than its factorization.

11111221011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 612.

The product of its (nonzero) digits is 4, while the sum is 12.

Adding to 11111221011 its reverse (11012211111), we get a palindrome (22123432122).

The spelling of 11111221011 in words is "eleven billion, one hundred eleven million, two hundred twenty-one thousand, eleven".