6421776828 has 24 divisors (see below), whose sum is σ = 14994456960. Its totient is φ = 2139119280.

The previous prime is 6421776827. The next prime is 6421776901. The reversal of 6421776828 is 8286771246.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6421776827) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 165888 + ... + 200903.

It is an arithmetic number, because the mean of its divisors is an integer number (624769040).

Almost surely, 2^6421776828 is an apocalyptic number.

It is an amenable number.

6421776828 is an abundant number, since it is smaller than the sum of its proper divisors (8572680132).

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

6421776828 is a wasteful number, since it uses less digits than its factorization.

6421776828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 368257 (or 368255 counting only the distinct ones).

The product of its digits is 1806336, while the sum is 51.

The square root of 6421776828 is about 80135.9895926917. The cubic root of 6421776828 is about 1858.7389637164.

The spelling of 6421776828 in words is "six billion, four hundred twenty-one million, seven hundred seventy-six thousand, eight hundred twenty-eight".