6399975 has 12 divisors (see below), whose sum is σ = 10581416. Its totient is φ = 3413280.

The previous prime is 6399971. The next prime is 6400013. The reversal of 6399975 is 5799936.

6399975 = T₁₁₇ + T₁₁₈ + ... + T₃₄₁.

It is a happy number.

It is not a de Polignac number, because 6399975 - 2² = 6399971 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6399971) 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, 42592 + ... + 42741.

Almost surely, 2^6399975 is an apocalyptic number.

6399975 is a deficient number, since it is larger than the sum of its proper divisors (4181441).

6399975 is a wasteful number, since it uses less digits than its factorization.

6399975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85346 (or 85341 counting only the distinct ones).

The product of its digits is 459270, while the sum is 48.

The square root of 6399975 is about 2529.8171870710. The cubic root of 6399975 is about 185.6633115948.

The spelling of 6399975 in words is "six million, three hundred ninety-nine thousand, nine hundred seventy-five".