12121111220 has 12 divisors (see below), whose sum is σ = 25454333604. Its totient is φ = 4848444480.

The previous prime is 12121111207. The next prime is 12121111243. The reversal of 12121111220 is 2211112121.

It can be written as a sum of positive squares in 2 ways, for example, as 2224442896 + 9896668324 = 47164^2 + 99482^2 .

It is a junction number, because it is equal to n+sod(n) for n = 12121111195 and 12121111204.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 303027761 + ... + 303027800.

It is an arithmetic number, because the mean of its divisors is an integer number (2121194467).

Almost surely, 2^12121111220 is an apocalyptic number.

12121111220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12121111220 is an abundant number, since it is smaller than the sum of its proper divisors (13333222384).

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

12121111220 is a wasteful number, since it uses less digits than its factorization.

12121111220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 606055570 (or 606055568 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 12121111220 its reverse (2211112121), we get a palindrome (14332223341).

Subtracting from 12121111220 its reverse (2211112121), we obtain a palindrome (9909999099).

The spelling of 12121111220 in words is "twelve billion, one hundred twenty-one million, one hundred eleven thousand, two hundred twenty".