642856500 has 576 divisors, whose sum is σ = 2537563392. Its totient is φ = 139968000.

The previous prime is 642856499. The next prime is 642856519. The reversal of 642856500 is 5658246.

642856500 is a `hidden beast` number, since 642 + 8 + 5 + 6 + 5 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 17374482 + ... + 17374518.

It is an arithmetic number, because the mean of its divisors is an integer number (4405492).

Almost surely, 2^642856500 is an apocalyptic number.

642856500 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642856500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1268781696).

642856500 is an abundant number, since it is smaller than the sum of its proper divisors (1894706892).

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

642856500 is a wasteful number, since it uses less digits than its factorization.

642856500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95 (or 71 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The square root of 642856500 is about 25354.6149645385. The cubic root of 642856500 is about 863.0540863123.

The spelling of 642856500 in words is "six hundred forty-two million, eight hundred fifty-six thousand, five hundred".