12123221220 has 144 divisors (see below), whose sum is σ = 42476773248. Its totient is φ = 2766074880.

The previous prime is 12123221167. The next prime is 12123221221. The reversal of 12123221220 is 2212232121.

12123221220 is a `hidden beast` number, since 121 + 2 + 322 + 1 + 220 = 666.

12123221220 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 12123221193 and 12123221202.

It is not an unprimeable number, because it can be changed into a prime (12123221221) 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 47 ways as a sum of consecutive naturals, for example, 146424 + ... + 213743.

It is an arithmetic number, because the mean of its divisors is an integer number (294977592).

Almost surely, 2^12123221220 is an apocalyptic number.

12123221220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12123221220 is an abundant number, since it is smaller than the sum of its proper divisors (30353552028).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12123221220 is a wasteful number, since it uses less digits than its factorization.

12123221220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360210 (or 360205 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 12123221220 its reverse (2212232121), we get a palindrome (14335453341).

The spelling of 12123221220 in words is "twelve billion, one hundred twenty-three million, two hundred twenty-one thousand, two hundred twenty".