642828 has 12 divisors (see below), whose sum is σ = 1499960. Its totient is φ = 214272.

The previous prime is 642809. The next prime is 642833. The reversal of 642828 is 828246.

It is a happy number.

642828 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 642795 and 642804.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 642828.

It is an unprimeable number.

642828 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26773 + ... + 26796.

2⁶⁴²⁸²⁸ is an apocalyptic number.

It is an amenable number.

642828 is an abundant number, since it is smaller than the sum of its proper divisors (857132).

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

642828 is a wasteful number, since it uses less digits than its factorization.

642828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53576 (or 53574 counting only the distinct ones).

The product of its digits is 6144, while the sum is 30.

The square root of 642828 is about 801.7655517668. The cubic root of 642828 is about 86.3041332090.

The spelling of 642828 in words is "six hundred forty-two thousand, eight hundred twenty-eight".