6441440 has 48 divisors (see below), whose sum is σ = 15386112. Its totient is φ = 2548224.

The previous prime is 6441439. The next prime is 6441467. The reversal of 6441440 is 441446.

It is an Ulam number.

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, 20162 + ... + 20478.

It is an arithmetic number, because the mean of its divisors is an integer number (320544).

Almost surely, 2^6441440 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 6441440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7693056).

6441440 is an abundant number, since it is smaller than the sum of its proper divisors (8944672).

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

6441440 is a wasteful number, since it uses less digits than its factorization.

6441440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 459 (or 451 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 23.

The square root of 6441440 is about 2537.9992119778. Note that the first 3 decimals coincide. The cubic root of 6441440 is about 186.0634153827.

Adding to 6441440 its reverse (441446), we get a palindrome (6882886).

The spelling of 6441440 in words is "six million, four hundred forty-one thousand, four hundred forty".