12021210121 has 4 divisors (see below), whose sum is σ = 12022020244. Its totient is φ = 12020400000.

The previous prime is 12021210059. The next prime is 12021210167. The reversal of 12021210121 is 12101212021.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4769836096 + 7251374025 = 69064^2 + 85155^2 .

It is a cyclic number.

It is not a de Polignac number, because 12021210121 - 2²¹ = 12019112969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12021211121) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 382380 + ... + 412621.

It is an arithmetic number, because the mean of its divisors is an integer number (3005505061).

Almost surely, 2^12021210121 is an apocalyptic number.

It is an amenable number.

12021210121 is a deficient number, since it is larger than the sum of its proper divisors (810123).

12021210121 is an equidigital number, since it uses as much as digits as its factorization.

12021210121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 810122.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 12021210121 its reverse (12101212021), we get a palindrome (24122422142).

The spelling of 12021210121 in words is "twelve billion, twenty-one million, two hundred ten thousand, one hundred twenty-one".