6645038759 has 4 divisors (see below), whose sum is σ = 6859394880. Its totient is φ = 6430682640.

The previous prime is 6645038749. The next prime is 6645038779. The reversal of 6645038759 is 9578305466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9578305466 = 2 ⋅4789152733.

It is a cyclic number.

It is not a de Polignac number, because 6645038759 - 2⁸ = 6645038503 is a prime.

It is a super-2 number, since 2×6645038759² = 88313080217224520162, which contains 22 as substring.

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 6645038759.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6645038749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107178014 + ... + 107178075.

It is an arithmetic number, because the mean of its divisors is an integer number (1714848720).

Almost surely, 2^6645038759 is an apocalyptic number.

6645038759 is a deficient number, since it is larger than the sum of its proper divisors (214356121).

6645038759 is a wasteful number, since it uses less digits than its factorization.

6645038759 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214356120.

The product of its (nonzero) digits is 5443200, while the sum is 53.

The square root of 6645038759 is about 81517.1071554922. The cubic root of 6645038759 is about 1880.0345888272.

The spelling of 6645038759 in words is "six billion, six hundred forty-five million, thirty-eight thousand, seven hundred fifty-nine".