6440440439 has 2 divisors, whose sum is σ = 6440440440. Its totient is φ = 6440440438.

The previous prime is 6440440423. The next prime is 6440440481. The reversal of 6440440439 is 9340440446.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6440440439 - 2⁴ = 6440440423 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6440443439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3220220219 + 3220220220.

It is an arithmetic number, because the mean of its divisors is an integer number (3220220220).

Almost surely, 2^6440440439 is an apocalyptic number.

6440440439 is a deficient number, since it is larger than the sum of its proper divisors (1).

6440440439 is an equidigital number, since it uses as much as digits as its factorization.

6440440439 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 165888, while the sum is 38.

The square root of 6440440439 is about 80252.3547255780. The cubic root of 6440440439 is about 1860.5379065314.

The spelling of 6440440439 in words is "six billion, four hundred forty million, four hundred forty thousand, four hundred thirty-nine".