12210001221 has 24 divisors (see below), whose sum is σ = 18378203872. Its totient is φ = 7199992800.

The previous prime is 12210001213. The next prime is 12210001241.

12210001221 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 12210001221 - 2³ = 12210001213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12210001197 and 12210001206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12210001211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 441115 + ... + 467976.

Almost surely, 2^12210001221 is an apocalyptic number.

12210001221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12210001221 is a deficient number, since it is larger than the sum of its proper divisors (6168202651).

12210001221 is a wasteful number, since it uses less digits than its factorization.

12210001221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 909153 (or 909142 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

It can be divided in two parts, 1221000 and 1221, that added together give a palindrome (1222221).

The spelling of 12210001221 in words is "twelve billion, two hundred ten million, one thousand, two hundred twenty-one".