221111221120121 has 2 divisors, whose sum is σ = 221111221120122. Its totient is φ = 221111221120120.

The previous prime is 221111221120109. The next prime is 221111221120129. The reversal of 221111221120121 is 121021122111122.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 221069169876025 + 42051244096 = 14868395^2 + 205064^2 .

It is a cyclic number.

It is not a de Polignac number, because 221111221120121 - 2³⁸ = 220836343213177 is a prime.

It is a super-2 number, since 2×221111221120121² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 221111221120093 and 221111221120102.

It is not a weakly prime, because it can be changed into another prime (221111221120129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110555610560060 + 110555610560061.

It is an arithmetic number, because the mean of its divisors is an integer number (110555610560061).

Almost surely, 2^{221111221120121} is an apocalyptic number.

It is an amenable number.

221111221120121 is a deficient number, since it is larger than the sum of its proper divisors (1).

221111221120121 is an equidigital number, since it uses as much as digits as its factorization.

221111221120121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 221111221120121 its reverse (121021122111122), we get a palindrome (342132343231243).

The spelling of 221111221120121 in words is "two hundred twenty-one trillion, one hundred eleven billion, two hundred twenty-one million, one hundred twenty thousand, one hundred twenty-one".