6443978 has 8 divisors (see below), whose sum is σ = 9676740. Its totient is φ = 3218400.

The previous prime is 6443977. The next prime is 6443981. The reversal of 6443978 is 8793446.

It can be written as a sum of positive squares in 2 ways, for example, as 6416089 + 27889 = 2533^2 + 167^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (6443977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2678 + ... + 4478.

Almost surely, 2^6443978 is an apocalyptic number.

6443978 is a deficient number, since it is larger than the sum of its proper divisors (3232762).

6443978 is a wasteful number, since it uses less digits than its factorization.

6443978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3592.

The product of its digits is 145152, while the sum is 41.

The square root of 6443978 is about 2538.4991628913. The cubic root of 6443978 is about 186.0878492019.

The spelling of 6443978 in words is "six million, four hundred forty-three thousand, nine hundred seventy-eight".