121221202221 has 24 divisors (see below), whose sum is σ = 200270266560. Its totient is φ = 69214193856.

The previous prime is 121221202169. The next prime is 121221202373. The reversal of 121221202221 is 122202122121.

It is a happy number.

121221202221 is a `hidden beast` number, since 1 + 21 + 221 + 202 + 221 = 666.

It is not a de Polignac number, because 121221202221 - 2¹⁴ = 121221185837 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121221202194 and 121221202203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221202121) 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 23 ways as a sum of consecutive naturals, for example, 684840 + ... + 843473.

It is an arithmetic number, because the mean of its divisors is an integer number (8344594440).

Almost surely, 2^121221202221 is an apocalyptic number.

It is an amenable number.

121221202221 is a deficient number, since it is larger than the sum of its proper divisors (79049064339).

121221202221 is a wasteful number, since it uses less digits than its factorization.

121221202221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1529585 (or 1529582 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 121221202221 its reverse (122202122121), we get a palindrome (243423324342).

The spelling of 121221202221 in words is "one hundred twenty-one billion, two hundred twenty-one million, two hundred two thousand, two hundred twenty-one".