12439993 has 4 divisors (see below), whose sum is σ = 12456180. Its totient is φ = 12423808.

The previous prime is 12439979. The next prime is 12440009. The reversal of 12439993 is 39993421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 39993421 = 13 ⋅3076417.

It can be written as a sum of positive squares in 2 ways, for example, as 12020089 + 419904 = 3467^2 + 648^2 .

It is a cyclic number.

It is not a de Polignac number, because 12439993 - 2¹³ = 12431801 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12439093) 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, 6880 + ... + 8497.

It is an arithmetic number, because the mean of its divisors is an integer number (3114045).

Almost surely, 2^12439993 is an apocalyptic number.

It is an amenable number.

12439993 is a deficient number, since it is larger than the sum of its proper divisors (16187).

12439993 is an equidigital number, since it uses as much as digits as its factorization.

12439993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16186.

The product of its digits is 52488, while the sum is 40.

The square root of 12439993 is about 3527.0374253756. The cubic root of 12439993 is about 231.7074754005.

It can be divided in two parts, 1243 and 9993, that added together give a square (11236 = 106²).

The spelling of 12439993 in words is "twelve million, four hundred thirty-nine thousand, nine hundred ninety-three".