6420985 has 8 divisors (see below), whose sum is σ = 8158536. Its totient is φ = 4834560.

The previous prime is 6420971. The next prime is 6420989. The reversal of 6420985 is 5890246.

It is a happy number.

6420985 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 1317904 + 5103081 = 1148^2 + 2259^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-6420985 is a prime.

It is a Duffinian number.

6420985 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 6420985.

It is not an unprimeable number, because it can be changed into a prime (6420989) 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, 37686 + ... + 37855.

It is an arithmetic number, because the mean of its divisors is an integer number (1019817).

Almost surely, 2^6420985 is an apocalyptic number.

It is an amenable number.

6420985 is a deficient number, since it is larger than the sum of its proper divisors (1737551).

6420985 is a wasteful number, since it uses less digits than its factorization.

6420985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75563.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 6420985 is about 2533.9662586546. The cubic root of 6420985 is about 185.8662564194.

The spelling of 6420985 in words is "six million, four hundred twenty thousand, nine hundred eighty-five".