6421885 has 8 divisors (see below), whose sum is σ = 7786296. Its totient is φ = 5084160.

The previous prime is 6421873. The next prime is 6421901. The reversal of 6421885 is 5881246.

It can be written as a sum of positive squares in 4 ways, for example, as 2377764 + 4044121 = 1542^2 + 2011^2 .

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-6421885 is a prime.

It is a Duffinian number.

6421885 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 6421885.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6136 + ... + 7105.

It is an arithmetic number, because the mean of its divisors is an integer number (973287).

Almost surely, 2^6421885 is an apocalyptic number.

It is an amenable number.

6421885 is a deficient number, since it is larger than the sum of its proper divisors (1364411).

6421885 is a wasteful number, since it uses less digits than its factorization.

6421885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13343.

The product of its digits is 15360, while the sum is 34.

The square root of 6421885 is about 2534.1438396429. The cubic root of 6421885 is about 185.8749400204.

The spelling of 6421885 in words is "six million, four hundred twenty-one thousand, eight hundred eighty-five".