121221220002221 has 4 divisors (see below), whose sum is σ = 121434262568700. Its totient is φ = 121008177435744.

The previous prime is 121221220002191. The next prime is 121221220002271. The reversal of 121221220002221 is 122200022122121.

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 70455794502025 + 50765425500196 = 8393795^2 + 7124986^2 .

It is a cyclic number.

It is not a de Polignac number, because 121221220002221 - 2¹⁸ = 121221219740077 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121221220002193 and 121221220002202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221220002271) 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, 106521282386 + ... + 106521283523.

It is an arithmetic number, because the mean of its divisors is an integer number (30358565642175).

Almost surely, 2^{121221220002221} is an apocalyptic number.

It is an amenable number.

121221220002221 is a deficient number, since it is larger than the sum of its proper divisors (213042566479).

121221220002221 is an equidigital number, since it uses as much as digits as its factorization.

121221220002221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213042566478.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 121221220002221 its reverse (122200022122121), we get a palindrome (243421242124342).

The spelling of 121221220002221 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, two hundred twenty million, two thousand, two hundred twenty-one".