6439925 has 12 divisors (see below), whose sum is σ = 8037060. Its totient is φ = 5118720.

The previous prime is 6439921. The next prime is 6439933. The reversal of 6439925 is 5299346.

It can be written as a sum of positive squares in 6 ways, for example, as 18769 + 6421156 = 137^2 + 2534^2 .

It is not a de Polignac number, because 6439925 - 2² = 6439921 is a prime.

It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6439921) 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, 3581 + ... + 5069.

It is an arithmetic number, because the mean of its divisors is an integer number (669755).

Almost surely, 2^6439925 is an apocalyptic number.

It is an amenable number.

6439925 is a deficient number, since it is larger than the sum of its proper divisors (1597135).

6439925 is a wasteful number, since it uses less digits than its factorization.

6439925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1672 (or 1667 counting only the distinct ones).

The product of its digits is 58320, while the sum is 38.

The square root of 6439925 is about 2537.7007309768. The cubic root of 6439925 is about 186.0488271242.

The spelling of 6439925 in words is "six million, four hundred thirty-nine thousand, nine hundred twenty-five".