12439809 has 6 divisors (see below), whose sum is σ = 17968626. Its totient is φ = 8293200.

The previous prime is 12439783. The next prime is 12439829. The reversal of 12439809 is 90893421.

It can be written as a sum of positive squares in only one way, i.e., 10400625 + 2039184 = 3225^2 + 1428^2 .

It is not a de Polignac number, because 12439809 - 2¹⁶ = 12374273 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12439829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 691092 + ... + 691109.

It is an arithmetic number, because the mean of its divisors is an integer number (2994771).

Almost surely, 2^12439809 is an apocalyptic number.

It is an amenable number.

12439809 is a deficient number, since it is larger than the sum of its proper divisors (5528817).

12439809 is a wasteful number, since it uses less digits than its factorization.

12439809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1382207 (or 1382204 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 12439809 is about 3527.0113410648. The cubic root of 12439809 is about 231.7063329994.

The spelling of 12439809 in words is "twelve million, four hundred thirty-nine thousand, eight hundred nine".