6438864 has 40 divisors (see below), whose sum is σ = 16954272. Its totient is φ = 2104960.

The previous prime is 6438833. The next prime is 6438871. The reversal of 6438864 is 4688346.

It is a super-2 number, since 2×6438864² = 82917939220992, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1279 + ... + 3809.

Almost surely, 2^6438864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6438864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8477136).

6438864 is an abundant number, since it is smaller than the sum of its proper divisors (10515408).

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

6438864 is a wasteful number, since it uses less digits than its factorization.

6438864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2595 (or 2589 counting only the distinct ones).

The product of its digits is 110592, while the sum is 39.

The square root of 6438864 is about 2537.4916748632. The cubic root of 6438864 is about 186.0386091663.

Adding to 6438864 its product of digits (110592), we get a palindrome (6549456).

The spelling of 6438864 in words is "six million, four hundred thirty-eight thousand, eight hundred sixty-four".