11205111522421 has 4 divisors (see below), whose sum is σ = 11205376504812. Its totient is φ = 11204846540032.

The previous prime is 11205111522317. The next prime is 11205111522443. The reversal of 11205111522421 is 12422511150211.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1360922895396 + 9844188627025 = 1166586^2 + 3137545^2 .

It is a cyclic number.

It is not a de Polignac number, because 11205111522421 - 2⁹ = 11205111521909 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11205111522421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11205111526421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 132427756 + ... + 132512341.

It is an arithmetic number, because the mean of its divisors is an integer number (2801344126203).

Almost surely, 2^{11205111522421} is an apocalyptic number.

It is an amenable number.

11205111522421 is a deficient number, since it is larger than the sum of its proper divisors (264982391).

11205111522421 is an equidigital number, since it uses as much as digits as its factorization.

11205111522421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 264982390.

The product of its (nonzero) digits is 1600, while the sum is 28.

Adding to 11205111522421 its reverse (12422511150211), we get a palindrome (23627622672632).

The spelling of 11205111522421 in words is "eleven trillion, two hundred five billion, one hundred eleven million, five hundred twenty-two thousand, four hundred twenty-one".