6421859 has 4 divisors (see below), whose sum is σ = 6428160. Its totient is φ = 6415560.

The previous prime is 6421843. The next prime is 6421873. The reversal of 6421859 is 9581246.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 6421859 - 2⁴ = 6421843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6421159) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1232 + ... + 3789.

It is an arithmetic number, because the mean of its divisors is an integer number (1607040).

Almost surely, 2^6421859 is an apocalyptic number.

6421859 is a deficient number, since it is larger than the sum of its proper divisors (6301).

6421859 is a wasteful number, since it uses less digits than its factorization.

6421859 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6300.

The product of its digits is 17280, while the sum is 35.

The square root of 6421859 is about 2534.1387097000. The cubic root of 6421859 is about 185.8746891722.

The spelling of 6421859 in words is "six million, four hundred twenty-one thousand, eight hundred fifty-nine".