6391986 has 8 divisors (see below), whose sum is σ = 12783984. Its totient is φ = 2130660.

The previous prime is 6391963. The next prime is 6391991. The reversal of 6391986 is 6891936.

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

6391986 is an admirable number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 532660 + ... + 532671.

It is an arithmetic number, because the mean of its divisors is an integer number (1597998).

Almost surely, 2^6391986 is an apocalyptic number.

6391986 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

6391986 is a wasteful number, since it uses less digits than its factorization.

6391986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1065336.

The product of its digits is 69984, while the sum is 42.

The square root of 6391986 is about 2528.2377261642. The cubic root of 6391986 is about 185.5860257823.

The spelling of 6391986 in words is "six million, three hundred ninety-one thousand, nine hundred eighty-six".