6442040 has 48 divisors (see below), whose sum is σ = 15944040. Its totient is φ = 2342560.

The previous prime is 6442039. The next prime is 6442049. The reversal of 6442040 is 402446.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6442049) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 585635 + ... + 585645.

Almost surely, 2^6442040 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 6442040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7972020).

6442040 is an abundant number, since it is smaller than the sum of its proper divisors (9502000).

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

6442040 is an frugal number, since it uses more digits than its factorization.

6442040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66 (or 18 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 6442040 is about 2538.1174125718. The cubic root of 6442040 is about 186.0691922785.

Adding to 6442040 its reverse (402446), we get a palindrome (6844486).

The spelling of 6442040 in words is "six million, four hundred forty-two thousand, forty".