6421128084 has 144 divisors (see below), whose sum is σ = 19206620160. Its totient is φ = 1770024960.

The previous prime is 6421128083. The next prime is 6421128127. The reversal of 6421128084 is 4808211246.

6421128084 is a `hidden beast` number, since 642 + 1 + 1 + 2 + 8 + 0 + 8 + 4 = 666.

It is a super-2 number, since 2×6421128084² = 82461771742267022112, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6421128083) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 3037812 + ... + 3039924.

Almost surely, 2^6421128084 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 6421128084, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9603310080).

6421128084 is an abundant number, since it is smaller than the sum of its proper divisors (12785492076).

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

6421128084 is a wasteful number, since it uses less digits than its factorization.

6421128084 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2550 (or 2545 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 36.

The square root of 6421128084 is about 80131.9417211389. The cubic root of 6421128084 is about 1858.6763701180.

The spelling of 6421128084 in words is "six billion, four hundred twenty-one million, one hundred twenty-eight thousand, eighty-four".