111221202122221 has 4 divisors (see below), whose sum is σ = 112033035714492. Its totient is φ = 110409368529952.

The previous prime is 111221202122197. The next prime is 111221202122227. The reversal of 111221202122221 is 122221202122111.

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 57651538165321 + 53569663956900 = 7592861^2 + 7319130^2 .

It is a cyclic number.

It is not a de Polignac number, because 111221202122221 - 2⁹ = 111221202121709 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 111221202122192 and 111221202122201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111221202122227) 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, 405916795930 + ... + 405916796203.

It is an arithmetic number, because the mean of its divisors is an integer number (28008258928623).

Almost surely, 2^{111221202122221} is an apocalyptic number.

It is an amenable number.

111221202122221 is a deficient number, since it is larger than the sum of its proper divisors (811833592271).

111221202122221 is an equidigital number, since it uses as much as digits as its factorization.

111221202122221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 811833592270.

The product of its (nonzero) digits is 256, while the sum is 22.

Adding to 111221202122221 its reverse (122221202122111), we get a palindrome (233442404244332).

The spelling of 111221202122221 in words is "one hundred eleven trillion, two hundred twenty-one billion, two hundred two million, one hundred twenty-two thousand, two hundred twenty-one".