6645039 has 4 divisors (see below), whose sum is σ = 8860056. Its totient is φ = 4430024.

The previous prime is 6645019. The next prime is 6645047. The reversal of 6645039 is 9305466.

It is a happy number.

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 6645039 - 2⁸ = 6644783 is a prime.

It is a D-number.

6645039 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6645019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1107504 + ... + 1107509.

It is an arithmetic number, because the mean of its divisors is an integer number (2215014).

Almost surely, 2^6645039 is an apocalyptic number.

6645039 is a deficient number, since it is larger than the sum of its proper divisors (2215017).

6645039 is a wasteful number, since it uses less digits than its factorization.

6645039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2215016.

The product of its (nonzero) digits is 19440, while the sum is 33.

The square root of 6645039 is about 2577.7973155390. The cubic root of 6645039 is about 188.0034611555.

The spelling of 6645039 in words is "six million, six hundred forty-five thousand, thirty-nine".