12011121221221 has 4 divisors (see below), whose sum is σ = 12011135629612. Its totient is φ = 12011106812832.

The previous prime is 12011121221179. The next prime is 12011121221233. The reversal of 12011121221221 is 12212212111021.

It is a happy number.

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 9845544093121 + 2165577128100 = 3137761^2 + 1471590^2 .

It is a cyclic number.

It is not a de Polignac number, because 12011121221221 - 2⁷ = 12011121221093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12011121221521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5871600 + ... + 7648393.

It is an arithmetic number, because the mean of its divisors is an integer number (3002783907403).

Almost surely, 2^{12011121221221} is an apocalyptic number.

It is an amenable number.

12011121221221 is a deficient number, since it is larger than the sum of its proper divisors (14408391).

12011121221221 is an equidigital number, since it uses as much as digits as its factorization.

12011121221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14408390.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 12011121221221 its reverse (12212212111021), we get a palindrome (24223333332242).

The spelling of 12011121221221 in words is "twelve trillion, eleven billion, one hundred twenty-one million, two hundred twenty-one thousand, two hundred twenty-one".