8640439 has 2 divisors, whose sum is σ = 8640440. Its totient is φ = 8640438.

The previous prime is 8640427. The next prime is 8640451. The reversal of 8640439 is 9340468.

It is a balanced prime because it is at equal distance from previous prime (8640427) and next prime (8640451).

It is a cyclic number.

It is not a de Polignac number, because 8640439 - 2⁵ = 8640407 is a prime.

It is a super-2 number, since 2×8640439² = 149314372225442, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8640409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4320219 + 4320220.

It is an arithmetic number, because the mean of its divisors is an integer number (4320220).

Almost surely, 2^8640439 is an apocalyptic number.

8640439 is a deficient number, since it is larger than the sum of its proper divisors (1).

8640439 is an equidigital number, since it uses as much as digits as its factorization.

8640439 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 8640439 is about 2939.4623658077. The cubic root of 8640439 is about 205.2005889101.

The spelling of 8640439 in words is "eight million, six hundred forty thousand, four hundred thirty-nine".