12121304320 has 72 divisors (see below), whose sum is σ = 29219728104. Its totient is φ = 4817559552.

The previous prime is 12121304311. The next prime is 12121304333. The reversal of 12121304320 is 2340312121.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 217621504 + 11903682816 = 14752^2 + 109104^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 170802 + ... + 231118.

It is an arithmetic number, because the mean of its divisors is an integer number (405829557).

Almost surely, 2^12121304320 is an apocalyptic number.

12121304320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12121304320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14609864052).

12121304320 is an abundant number, since it is smaller than the sum of its proper divisors (17098423784).

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

12121304320 is an equidigital number, since it uses as much as digits as its factorization.

12121304320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60495 (or 60481 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 12121304320 its reverse (2340312121), we get a palindrome (14461616441).

The spelling of 12121304320 in words is "twelve billion, one hundred twenty-one million, three hundred four thousand, three hundred twenty".