6387639 has 4 divisors (see below), whose sum is σ = 8516856. Its totient is φ = 4258424.

The previous prime is 6387637. The next prime is 6387649. The reversal of 6387639 is 9367836.

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 6387639 - 2¹ = 6387637 is a prime.

It is a D-number.

6387639 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 6387639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6387637) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1064604 + ... + 1064609.

It is an arithmetic number, because the mean of its divisors is an integer number (2129214).

Almost surely, 2^6387639 is an apocalyptic number.

6387639 is a deficient number, since it is larger than the sum of its proper divisors (2129217).

6387639 is a wasteful number, since it uses less digits than its factorization.

6387639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2129216.

The product of its digits is 163296, while the sum is 42.

The square root of 6387639 is about 2527.3778902254. The cubic root of 6387639 is about 185.5439457254.

The spelling of 6387639 in words is "six million, three hundred eighty-seven thousand, six hundred thirty-nine".