6421428438 has 16 divisors (see below), whose sum is σ = 12850627440. Its totient is φ = 2139181056.

The previous prime is 6421428407. The next prime is 6421428449. The reversal of 6421428438 is 8348241246.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 6421428438.

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, 313003 + ... + 332886.

It is an arithmetic number, because the mean of its divisors is an integer number (803164215).

Almost surely, 2^6421428438 is an apocalyptic number.

6421428438 is an abundant number, since it is smaller than the sum of its proper divisors (6429199002).

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

6421428438 is a wasteful number, since it uses less digits than its factorization.

6421428438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 647551.

The product of its digits is 294912, while the sum is 42.

The square root of 6421428438 is about 80133.8158207882. The cubic root of 6421428438 is about 1858.7053500818.

The spelling of 6421428438 in words is "six billion, four hundred twenty-one million, four hundred twenty-eight thousand, four hundred thirty-eight".