121201220221 has 4 divisors (see below), whose sum is σ = 121829206012. Its totient is φ = 120573234432.

The previous prime is 121201220183. The next prime is 121201220227. The reversal of 121201220221 is 122022102121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122022102121 = 17 ⋅7177770713.

It can be written as a sum of positive squares in 2 ways, for example, as 10321544025 + 110879676196 = 101595^2 + 332986^2 .

It is a cyclic number.

It is not a de Polignac number, because 121201220221 - 2¹⁹ = 121200695933 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121201220195 and 121201220204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121201220227) 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, 313992606 + ... + 313992991.

It is an arithmetic number, because the mean of its divisors is an integer number (30457301503).

Almost surely, 2^121201220221 is an apocalyptic number.

It is an amenable number.

121201220221 is a deficient number, since it is larger than the sum of its proper divisors (627985791).

121201220221 is an equidigital number, since it uses as much as digits as its factorization.

121201220221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 627985790.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 121201220221 its reverse (122022102121), we get a palindrome (243223322342).

The spelling of 121201220221 in words is "one hundred twenty-one billion, two hundred one million, two hundred twenty thousand, two hundred twenty-one".