6421859808 has 384 divisors, whose sum is σ = 22369665024. Its totient is φ = 1566259200.

The previous prime is 6421859783. The next prime is 6421859833. The reversal of 6421859808 is 8089581246.

It is an interprime number because it is at equal distance from previous prime (6421859783) and next prime (6421859833).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 6228253 + ... + 6229283.

It is an arithmetic number, because the mean of its divisors is an integer number (58254336).

Almost surely, 2^6421859808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6421859808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11184832512).

6421859808 is an abundant number, since it is smaller than the sum of its proper divisors (15947805216).

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

6421859808 is a wasteful number, since it uses less digits than its factorization.

6421859808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1118 (or 1110 counting only the distinct ones).

The product of its (nonzero) digits is 1105920, while the sum is 51.

The square root of 6421859808 is about 80136.5073359202. The cubic root of 6421859808 is about 1858.7469696779.

The spelling of 6421859808 in words is "six billion, four hundred twenty-one million, eight hundred fifty-nine thousand, eight hundred eight".