11212120212221 has 4 divisors (see below), whose sum is σ = 11338099091100. Its totient is φ = 11086141333344.

The previous prime is 11212120212211. The next prime is 11212120212229. The reversal of 11212120212221 is 12221202121211.

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 794647444900 + 10417472767321 = 891430^2 + 3227611^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11212120212221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11212120212193 and 11212120212202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11212120212229) 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, 62989439306 + ... + 62989439483.

It is an arithmetic number, because the mean of its divisors is an integer number (2834524772775).

Almost surely, 2^{11212120212221} is an apocalyptic number.

It is an amenable number.

11212120212221 is a deficient number, since it is larger than the sum of its proper divisors (125978878879).

11212120212221 is an equidigital number, since it uses as much as digits as its factorization.

11212120212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125978878878.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 11212120212221 its reverse (12221202121211), we get a palindrome (23433322333432).

The spelling of 11212120212221 in words is "eleven trillion, two hundred twelve billion, one hundred twenty million, two hundred twelve thousand, two hundred twenty-one".