12161201221 has 8 divisors (see below), whose sum is σ = 13097603960. Its totient is φ = 11224930752.

The previous prime is 12161201197. The next prime is 12161201257. The reversal of 12161201221 is 12210216121.

12161201221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 871076196 + 11290125025 = 29514^2 + 106255^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12161201221 - 2⁵ = 12161201189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12161201281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 243811 + ... + 289423.

It is an arithmetic number, because the mean of its divisors is an integer number (1637200495).

Almost surely, 2^12161201221 is an apocalyptic number.

It is an amenable number.

12161201221 is a deficient number, since it is larger than the sum of its proper divisors (936402739).

12161201221 is a wasteful number, since it uses less digits than its factorization.

12161201221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66135.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 12161201221 its reverse (12210216121), we get a palindrome (24371417342).

The spelling of 12161201221 in words is "twelve billion, one hundred sixty-one million, two hundred one thousand, two hundred twenty-one".