12643321 has 4 divisors (see below), whose sum is σ = 12658932. Its totient is φ = 12627712.

The previous prime is 12643313. The next prime is 12643349. The reversal of 12643321 is 12334621.

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 9363600 + 3279721 = 3060^2 + 1811^2 .

It is a cyclic number.

It is not a de Polignac number, because 12643321 - 2³ = 12643313 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12643292 and 12643301.

It is not an unprimeable number, because it can be changed into a prime (12643361) 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, 6520 + ... + 8233.

It is an arithmetic number, because the mean of its divisors is an integer number (3164733).

Almost surely, 2^12643321 is an apocalyptic number.

It is an amenable number.

12643321 is a deficient number, since it is larger than the sum of its proper divisors (15611).

12643321 is an equidigital number, since it uses as much as digits as its factorization.

12643321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15610.

The product of its digits is 864, while the sum is 22.

The square root of 12643321 is about 3555.7447883671. The cubic root of 12643321 is about 232.9630560274.

Adding to 12643321 its reverse (12334621), we get a palindrome (24977942).

The spelling of 12643321 in words is "twelve million, six hundred forty-three thousand, three hundred twenty-one".