6440704 has 36 divisors (see below), whose sum is σ = 13020280. Its totient is φ = 3179520.

The previous prime is 6440699. The next prime is 6440723. The reversal of 6440704 is 4070446.

It is a happy number.

It is a hoax number, since the sum of its digits (25) coincides with the sum of the digits of its distinct prime factors.

It is an Ulam number.

It is a plaindrome in base 13.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35494 + ... + 35674.

Almost surely, 2^6440704 is an apocalyptic number.

6440704 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6440704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6510140).

6440704 is an abundant number, since it is smaller than the sum of its proper divisors (6579576).

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

6440704 is a wasteful number, since it uses less digits than its factorization.

6440704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336 (or 322 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 25.

The square root of 6440704 is about 2537.8542117308. The cubic root of 6440704 is about 186.0563285673.

The spelling of 6440704 in words is "six million, four hundred forty thousand, seven hundred four".