12321155220 has 192 divisors, whose sum is σ = 39154655232. Its totient is φ = 2867904000.

The previous prime is 12321155183. The next prime is 12321155239. The reversal of 12321155220 is 2255112321.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2677962 + ... + 2682558.

It is an arithmetic number, because the mean of its divisors is an integer number (203930496).

Almost surely, 2^12321155220 is an apocalyptic number.

12321155220 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 12321155220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19577327616).

12321155220 is an abundant number, since it is smaller than the sum of its proper divisors (26833500012).

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

12321155220 is a wasteful number, since it uses less digits than its factorization.

12321155220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4782 (or 4780 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 24.

Adding to 12321155220 its reverse (2255112321), we get a palindrome (14576267541).

The spelling of 12321155220 in words is "twelve billion, three hundred twenty-one million, one hundred fifty-five thousand, two hundred twenty".