121221122212221 has 16 divisors (see below), whose sum is σ = 161642918255808. Its totient is φ = 80806704249600.

The previous prime is 121221122212199. The next prime is 121221122212241. The reversal of 121221122212221 is 122212221122121.

It is not a de Polignac number, because 121221122212221 - 2¹⁰ = 121221122211197 is a prime.

It is a super-3 number, since 3×121221122212221³ (a number of 43 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 121221122212191 and 121221122212200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221122212241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2746825326 + ... + 2746869456.

It is an arithmetic number, because the mean of its divisors is an integer number (10102682390988).

Almost surely, 2^{121221122212221} is an apocalyptic number.

It is an amenable number.

121221122212221 is a deficient number, since it is larger than the sum of its proper divisors (40421796043587).

121221122212221 is a wasteful number, since it uses less digits than its factorization.

121221122212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106972.

The product of its digits is 512, while the sum is 24.

Adding to 121221122212221 its reverse (122212221122121), we get a palindrome (243433343334342).

The spelling of 121221122212221 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, one hundred twenty-two million, two hundred twelve thousand, two hundred twenty-one".