11111011221 has 8 divisors (see below), whose sum is σ = 14876154304. Its totient is φ = 7376604480.

The previous prime is 11111011207. The next prime is 11111011243. The reversal of 11111011221 is 12211011111.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 11111011221 - 2¹⁵ = 11110978453 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11111011197 and 11111011206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11111011291) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7683241 + ... + 7684686.

It is an arithmetic number, because the mean of its divisors is an integer number (1859519288).

Almost surely, 2^11111011221 is an apocalyptic number.

It is an amenable number.

11111011221 is a deficient number, since it is larger than the sum of its proper divisors (3765143083).

11111011221 is a wasteful number, since it uses less digits than its factorization.

11111011221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15368171.

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

Adding to 11111011221 its reverse (12211011111), we get a palindrome (23322022332).

The spelling of 11111011221 in words is "eleven billion, one hundred eleven million, eleven thousand, two hundred twenty-one".