11111011312221 has 24 divisors (see below), whose sum is σ = 16510428023544. Its totient is φ = 7195150425600.

The previous prime is 11111011312153. The next prime is 11111011312253. The reversal of 11111011312221 is 12221311011111.

11111011312221 is a `hidden beast` number, since 1 + 11 + 110 + 11 + 312 + 221 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 4986351524196 + 6124659788025 = 2233014^2 + 2474805^2 .

It is not a de Polignac number, because 11111011312221 - 2¹⁸ = 11111011050077 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11111011312194 and 11111011312203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11111011312321) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27558936 + ... + 27959201.

It is an arithmetic number, because the mean of its divisors is an integer number (687934500981).

Almost surely, 2^{11111011312221} is an apocalyptic number.

It is an amenable number.

11111011312221 is a deficient number, since it is larger than the sum of its proper divisors (5399416711323).

11111011312221 is a wasteful number, since it uses less digits than its factorization.

11111011312221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55518781 (or 55518778 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 18.

Adding to 11111011312221 its reverse (12221311011111), we get a palindrome (23332322323332).

The spelling of 11111011312221 in words is "eleven trillion, one hundred eleven billion, eleven million, three hundred twelve thousand, two hundred twenty-one".