12123220 has 24 divisors (see below), whose sum is σ = 25941384. Its totient is φ = 4757376.

The previous prime is 12123217. The next prime is 12123239. The reversal of 12123220 is 2232121.

It can be written as a sum of positive squares in 4 ways, for example, as 1285956 + 10837264 = 1134^2 + 3292^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 12123220.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4659 + ... + 6778.

It is an arithmetic number, because the mean of its divisors is an integer number (1080891).

Almost surely, 2^12123220 is an apocalyptic number.

12123220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12123220 is an abundant number, since it is smaller than the sum of its proper divisors (13818164).

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

12123220 is a wasteful number, since it uses less digits than its factorization.

12123220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11499 (or 11497 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 12123220 is about 3481.8414668103. The cubic root of 12123220 is about 229.7238020429.

Adding to 12123220 its reverse (2232121), we get a palindrome (14355341).

The spelling of 12123220 in words is "twelve million, one hundred twenty-three thousand, two hundred twenty".