12121221123 has 48 divisors (see below), whose sum is σ = 20039764992. Its totient is φ = 6992568000.

The previous prime is 12121221121. The next prime is 12121221137. The reversal of 12121221123 is 32112212121.

It is not a de Polignac number, because 12121221123 - 2¹ = 12121221121 is a prime.

It is a super-2 number, since 2×12121221123² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 12121221096 and 12121221105.

It is not an unprimeable number, because it can be changed into a prime (12121221121) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 154836 + ... + 219582.

It is an arithmetic number, because the mean of its divisors is an integer number (417495104).

Almost surely, 2^12121221123 is an apocalyptic number.

12121221123 is a deficient number, since it is larger than the sum of its proper divisors (7918543869).

12121221123 is a wasteful number, since it uses less digits than its factorization.

12121221123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64856 (or 64853 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

Adding to 12121221123 its reverse (32112212121), we get a palindrome (44233433244).

The spelling of 12121221123 in words is "twelve billion, one hundred twenty-one million, two hundred twenty-one thousand, one hundred twenty-three".