12121221231 has 12 divisors (see below), whose sum is σ = 20009635152. Its totient is φ = 6926412096.

The previous prime is 12121221227. The next prime is 12121221239. The reversal of 12121221231 is 13212212121.

12121221231 is a `hidden beast` number, since 1 + 212 + 1 + 221 + 231 = 666.

It is not a de Polignac number, because 12121221231 - 2² = 12121221227 is a prime.

It is a super-2 number, since 2×12121221231² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12121221239) 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 11 ways as a sum of consecutive naturals, for example, 96200106 + ... + 96200231.

It is an arithmetic number, because the mean of its divisors is an integer number (1667469596).

Almost surely, 2^12121221231 is an apocalyptic number.

12121221231 is a deficient number, since it is larger than the sum of its proper divisors (7888413921).

12121221231 is a wasteful number, since it uses less digits than its factorization.

12121221231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192400350 (or 192400347 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

Adding to 12121221231 its reverse (13212212121), we get a palindrome (25333433352).

The spelling of 12121221231 in words is "twelve billion, one hundred twenty-one million, two hundred twenty-one thousand, two hundred thirty-one".