6398978 has 8 divisors (see below), whose sum is σ = 9691968. Its totient is φ = 3168324.

The previous prime is 6398941. The next prime is 6398981. The reversal of 6398978 is 8798936.

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

It is an Ulam number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15326 + ... + 15737.

It is an arithmetic number, because the mean of its divisors is an integer number (1211496).

Almost surely, 2^6398978 is an apocalyptic number.

6398978 is a deficient number, since it is larger than the sum of its proper divisors (3292990).

6398978 is a wasteful number, since it uses less digits than its factorization.

6398978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31168.

The product of its digits is 653184, while the sum is 50.

The square root of 6398978 is about 2529.6201295847. The cubic root of 6398978 is about 185.6536701022.

The spelling of 6398978 in words is "six million, three hundred ninety-eight thousand, nine hundred seventy-eight".