6511978 has 24 divisors (see below), whose sum is σ = 10916640. Its totient is φ = 2910600.

The previous prime is 6511961. The next prime is 6511997. The reversal of 6511978 is 8791156.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 16993 + ... + 17371.

It is an arithmetic number, because the mean of its divisors is an integer number (454860).

Almost surely, 2^6511978 is an apocalyptic number.

6511978 is a deficient number, since it is larger than the sum of its proper divisors (4404662).

6511978 is a wasteful number, since it uses less digits than its factorization.

6511978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 474 (or 463 counting only the distinct ones).

The product of its digits is 15120, while the sum is 37.

The square root of 6511978 is about 2551.8577546564. The cubic root of 6511978 is about 186.7401234422.

The spelling of 6511978 in words is "six million, five hundred eleven thousand, nine hundred seventy-eight".