11221121220121 has 4 divisors (see below), whose sum is σ = 11221164875700. Its totient is φ = 11221077564544.

The previous prime is 11221121220103. The next prime is 11221121220131. The reversal of 11221121220121 is 12102212112211.

It is a happy number.

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 4089337328521 + 7131783891600 = 2022211^2 + 2670540^2 .

It is a cyclic number.

It is not a de Polignac number, because 11221121220121 - 2¹³ = 11221121211929 is a prime.

It is a super-2 number, since 2×11221121220121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11221121220131) 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, 21439936 + ... + 21957073.

It is an arithmetic number, because the mean of its divisors is an integer number (2805291218925).

Almost surely, 2^{11221121220121} is an apocalyptic number.

It is an amenable number.

11221121220121 is a deficient number, since it is larger than the sum of its proper divisors (43655579).

11221121220121 is an equidigital number, since it uses as much as digits as its factorization.

11221121220121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43655578.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 11221121220121 its reverse (12102212112211), we get a palindrome (23323333332332).

The spelling of 11221121220121 in words is "eleven trillion, two hundred twenty-one billion, one hundred twenty-one million, two hundred twenty thousand, one hundred twenty-one".