12440839 has 4 divisors (see below), whose sum is σ = 13095640. Its totient is φ = 11786040.

The previous prime is 12440819. The next prime is 12440851. The reversal of 12440839 is 93804421.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 12440839 - 2⁷ = 12440711 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12440839.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12440809) 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, 327372 + ... + 327409.

It is an arithmetic number, because the mean of its divisors is an integer number (3273910).

Almost surely, 2^12440839 is an apocalyptic number.

12440839 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

12440839 is a deficient number, since it is larger than the sum of its proper divisors (654801).

12440839 is an equidigital number, since it uses as much as digits as its factorization.

12440839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 654800.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 12440839 is about 3527.1573540175. The cubic root of 12440839 is about 231.7127278172.

The spelling of 12440839 in words is "twelve million, four hundred forty thousand, eight hundred thirty-nine".