6420978 has 16 divisors (see below), whose sum is σ = 14268960. Its totient is φ = 2140308.

The previous prime is 6420971. The next prime is 6420989. The reversal of 6420978 is 8790246.

6420978 is a `hidden beast` number, since 642 + 0 + 9 + 7 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (6420971) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59400 + ... + 59507.

It is an arithmetic number, because the mean of its divisors is an integer number (891810).

Almost surely, 2^6420978 is an apocalyptic number.

6420978 is an abundant number, since it is smaller than the sum of its proper divisors (7847982).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6420978 is a wasteful number, since it uses less digits than its factorization.

6420978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118918 (or 118912 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 6420978 is about 2533.9648774204. The cubic root of 6420978 is about 185.8661888771.

The spelling of 6420978 in words is "six million, four hundred twenty thousand, nine hundred seventy-eight".