642984 has 32 divisors (see below), whose sum is σ = 1633920. Its totient is φ = 210816.

The previous prime is 642977. The next prime is 642997. The reversal of 642984 is 489246.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 642984.

It is an unprimeable number.

642984 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1569 + ... + 1935.

It is an arithmetic number, because the mean of its divisors is an integer number (51060).

2⁶⁴²⁹⁸⁴ is an apocalyptic number.

It is an amenable number.

642984 is an abundant number, since it is smaller than the sum of its proper divisors (990936).

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

642984 is a wasteful number, since it uses less digits than its factorization.

642984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 449 (or 445 counting only the distinct ones).

The product of its digits is 13824, while the sum is 33.

The square root of 642984 is about 801.8628311625. The cubic root of 642984 is about 86.3111140062.

The spelling of 642984 in words is "six hundred forty-two thousand, nine hundred eighty-four".