6439540 has 24 divisors (see below), whose sum is σ = 14112000. Its totient is φ = 2463648.

The previous prime is 6439519. The next prime is 6439541. The reversal of 6439540 is 459346.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6439541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6540 + ... + 7459.

It is an arithmetic number, because the mean of its divisors is an integer number (588000).

Almost surely, 2^6439540 is an apocalyptic number.

It is an amenable number.

6439540 is an abundant number, since it is smaller than the sum of its proper divisors (7672460).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6439540 is a wasteful number, since it uses less digits than its factorization.

6439540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14031 (or 14029 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 31.

The square root of 6439540 is about 2537.6248737747. The cubic root of 6439540 is about 186.0451195124.

The spelling of 6439540 in words is "six million, four hundred thirty-nine thousand, five hundred forty".