6440007 has 16 divisors (see below), whose sum is σ = 9849600. Its totient is φ = 3666432.

The previous prime is 6440003. The next prime is 6440011. The reversal of 6440007 is 7000446.

It is an interprime number because it is at equal distance from previous prime (6440003) and next prime (6440011).

It is not a de Polignac number, because 6440007 - 2² = 6440003 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

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

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9088 + ... + 9770.

It is an arithmetic number, because the mean of its divisors is an integer number (615600).

Almost surely, 2^6440007 is an apocalyptic number.

6440007 is a deficient number, since it is larger than the sum of its proper divisors (3409593).

6440007 is a wasteful number, since it uses less digits than its factorization.

6440007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1142.

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 6440007 is about 2537.7168872827. The cubic root of 6440007 is about 186.0496167782.

The spelling of 6440007 in words is "six million, four hundred forty thousand, seven".