6428821 has 8 divisors (see below), whose sum is σ = 7734080. Its totient is φ = 5220288.

The previous prime is 6428819. The next prime is 6428827. The reversal of 6428821 is 1288246.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6428821 - 2¹ = 6428819 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6428827) 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, 24036 + ... + 24301.

It is an arithmetic number, because the mean of its divisors is an integer number (966760).

Almost surely, 2^6428821 is an apocalyptic number.

It is an amenable number.

6428821 is a deficient number, since it is larger than the sum of its proper divisors (1305259).

6428821 is a wasteful number, since it uses less digits than its factorization.

6428821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48363.

The product of its digits is 6144, while the sum is 31.

The square root of 6428821 is about 2535.5119798573. The cubic root of 6428821 is about 185.9418344351.

The spelling of 6428821 in words is "six million, four hundred twenty-eight thousand, eight hundred twenty-one".