12665133212021 has 4 divisors (see below), whose sum is σ = 13101861943500. Its totient is φ = 12228404480544.

The previous prime is 12665133211999. The next prime is 12665133212023. The reversal of 12665133212021 is 12021233156621.

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 5517472144900 + 7147661067121 = 2348930^2 + 2673511^2 .

It is a cyclic number.

It is not a de Polignac number, because 12665133212021 - 2⁶ = 12665133211957 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 (12665133212023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 218364365696 + ... + 218364365753.

It is an arithmetic number, because the mean of its divisors is an integer number (3275465485875).

Almost surely, 2^{12665133212021} is an apocalyptic number.

It is an amenable number.

12665133212021 is a deficient number, since it is larger than the sum of its proper divisors (436728731479).

12665133212021 is an equidigital number, since it uses as much as digits as its factorization.

12665133212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 436728731478.

The product of its (nonzero) digits is 25920, while the sum is 35.

Adding to 12665133212021 its reverse (12021233156621), we get a palindrome (24686366368642).

The spelling of 12665133212021 in words is "twelve trillion, six hundred sixty-five billion, one hundred thirty-three million, two hundred twelve thousand, twenty-one".