12340021 has 4 divisors (see below), whose sum is σ = 12348000. Its totient is φ = 12332044.

The previous prime is 12340007. The next prime is 12340033. The reversal of 12340021 is 12004321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 12340021 - 2¹³ = 12331829 is a prime.

It is a super-2 number, since 2×12340021² = 304552236560882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12339983 and 12340010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12340061) 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, 841 + ... + 5038.

It is an arithmetic number, because the mean of its divisors is an integer number (3087000).

Almost surely, 2^12340021 is an apocalyptic number.

It is an amenable number.

12340021 is a deficient number, since it is larger than the sum of its proper divisors (7979).

12340021 is an equidigital number, since it uses as much as digits as its factorization.

12340021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7978.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 12340021 is about 3512.8366030887. The cubic root of 12340021 is about 231.0851119685.

Adding to 12340021 its reverse (12004321), we get a palindrome (24344342).

The spelling of 12340021 in words is "twelve million, three hundred forty thousand, twenty-one".