11111122121201 has 4 divisors (see below), whose sum is σ = 11167523756532. Its totient is φ = 11054720485872.

The previous prime is 11111122121159. The next prime is 11111122121213. The reversal of 11111122121201 is 10212122111111.

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 6533238240400 + 4577883880801 = 2556020^2 + 2139599^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11111122121201 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 11111122121201.

It is not an unprimeable number, because it can be changed into a prime (11111122121251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28200817370 + ... + 28200817763.

It is an arithmetic number, because the mean of its divisors is an integer number (2791880939133).

Almost surely, 2^{11111122121201} is an apocalyptic number.

It is an amenable number.

11111122121201 is a deficient number, since it is larger than the sum of its proper divisors (56401635331).

11111122121201 is an equidigital number, since it uses as much as digits as its factorization.

11111122121201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56401635330.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 11111122121201 its reverse (10212122111111), we get a palindrome (21323244232312).

The spelling of 11111122121201 in words is "eleven trillion, one hundred eleven billion, one hundred twenty-two million, one hundred twenty-one thousand, two hundred one".