6440001 has 16 divisors (see below), whose sum is σ = 9004800. Its totient is φ = 4088448.

The previous prime is 6439997. The next prime is 6440003. The reversal of 6440001 is 1000446.

It is not a de Polignac number, because 6440001 - 2² = 6439997 is a prime.

It is a super-2 number, since 2×6440001² = 82947225760002, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6440003) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 6405 + ... + 7341.

It is an arithmetic number, because the mean of its divisors is an integer number (562800).

Almost surely, 2^6440001 is an apocalyptic number.

It is an amenable number.

6440001 is a deficient number, since it is larger than the sum of its proper divisors (2564799).

6440001 is a wasteful number, since it uses less digits than its factorization.

6440001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1048.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 6440001 is about 2537.7157051175. The cubic root of 6440001 is about 186.0495589989.

Adding to 6440001 its reverse (1000446), we get a palindrome (7440447).

The spelling of 6440001 in words is "six million, four hundred forty thousand, one".