11011211221221 has 32 divisors (see below), whose sum is σ = 16343831427840. Its totient is φ = 7326903513600.

The previous prime is 11011211221183. The next prime is 11011211221229. The reversal of 11011211221221 is 12212211211011.

It is a happy number.

11011211221221 is a `hidden beast` number, since 1 + 1 + 0 + 11 + 211 + 221 + 221 = 666.

It is not a de Polignac number, because 11011211221221 - 2⁷ = 11011211221093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11011211221194 and 11011211221203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11011211221229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31247416 + ... + 31597838.

It is an arithmetic number, because the mean of its divisors is an integer number (510744732120).

Almost surely, 2^{11011211221221} is an apocalyptic number.

It is an amenable number.

11011211221221 is a deficient number, since it is larger than the sum of its proper divisors (5332620206619).

11011211221221 is a wasteful number, since it uses less digits than its factorization.

11011211221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 352634 (or 352628 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

Adding to 11011211221221 its reverse (12212211211011), we get a palindrome (23223422432232).

The spelling of 11011211221221 in words is "eleven trillion, eleven billion, two hundred eleven million, two hundred twenty-one thousand, two hundred twenty-one".