6449999 has 4 divisors (see below), whose sum is σ = 6470664. Its totient is φ = 6429336.

The previous prime is 6449923. The next prime is 6450007. The reversal of 6449999 is 9999446.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6449999 - 2⁸ = 6449743 is a prime.

It is a Duffinian number.

6449999 is a modest number, since divided by 9999 gives 644 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6449909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9857 + ... + 10490.

It is an arithmetic number, because the mean of its divisors is an integer number (1617666).

Almost surely, 2^6449999 is an apocalyptic number.

6449999 is a deficient number, since it is larger than the sum of its proper divisors (20665).

6449999 is a wasteful number, since it uses less digits than its factorization.

6449999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20664.

The product of its digits is 629856, while the sum is 50.

The square root of 6449999 is about 2539.6848229652. The cubic root of 6449999 is about 186.1457888864.

The spelling of 6449999 in words is "six million, four hundred forty-nine thousand, nine hundred ninety-nine".