6421428408 has 16 divisors (see below), whose sum is σ = 16053571080. Its totient is φ = 2140476128.

The previous prime is 6421428407. The next prime is 6421428449. The reversal of 6421428408 is 8048241246.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6421428401) 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, 133779735 + ... + 133779782.

Almost surely, 2^6421428408 is an apocalyptic number.

It is an amenable number.

6421428408 is an abundant number, since it is smaller than the sum of its proper divisors (9632142672).

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

6421428408 is a wasteful number, since it uses less digits than its factorization.

6421428408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267559526 (or 267559522 counting only the distinct ones).

The product of its (nonzero) digits is 98304, while the sum is 39.

The square root of 6421428408 is about 80133.8156336013. The cubic root of 6421428408 is about 1858.7053471873.

The spelling of 6421428408 in words is "six billion, four hundred twenty-one million, four hundred twenty-eight thousand, four hundred eight".