12211111212121 has 8 divisors (see below), whose sum is σ = 12442828422024. Its totient is φ = 11979442849920.

The previous prime is 12211111212107. The next prime is 12211111212211. The reversal of 12211111212121 is 12121211111221.

It can be written as a sum of positive squares in 4 ways, for example, as 1955354755600 + 10255756456521 = 1398340^2 + 3202461^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12211111212121 - 2⁹ = 12211111211609 is a prime.

It is a super-2 number, since 2×12211111212121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12211111212221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11707020 + ... + 12707341.

It is an arithmetic number, because the mean of its divisors is an integer number (1555353552753).

Almost surely, 2^{12211111212121} is an apocalyptic number.

It is an amenable number.

12211111212121 is a deficient number, since it is larger than the sum of its proper divisors (231717209903).

12211111212121 is an equidigital number, since it uses as much as digits as its factorization.

12211111212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24423851.

The product of its digits is 32, while the sum is 19.

Adding to 12211111212121 its reverse (12121211111221), we get a palindrome (24332322323342).

The spelling of 12211111212121 in words is "twelve trillion, two hundred eleven billion, one hundred eleven million, two hundred twelve thousand, one hundred twenty-one".