12026821 has 4 divisors (see below), whose sum is σ = 12224044. Its totient is φ = 11829600.

The previous prime is 12026809. The next prime is 12026827. The reversal of 12026821 is 12862021.

12026821 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 6964321 + 5062500 = 2639^2 + 2250^2 .

It is a cyclic number.

It is not a de Polignac number, because 12026821 - 2¹⁷ = 11895749 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12026792 and 12026801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12026827) 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, 98520 + ... + 98641.

It is an arithmetic number, because the mean of its divisors is an integer number (3056011).

Almost surely, 2^12026821 is an apocalyptic number.

It is an amenable number.

12026821 is a deficient number, since it is larger than the sum of its proper divisors (197223).

12026821 is an equidigital number, since it uses as much as digits as its factorization.

12026821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197222.

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 12026821 is about 3467.9707322871. The cubic root of 12026821 is about 229.1132903714.

Adding to 12026821 its reverse (12862021), we get a palindrome (24888842).

It can be divided in two parts, 120268 and 21, that multiplied together give a triangular number (2525628 = T₂₂₄₇).

The spelling of 12026821 in words is "twelve million, twenty-six thousand, eight hundred twenty-one".