643820082 has 8 divisors (see below), whose sum is σ = 1287640176. Its totient is φ = 214606692.

The previous prime is 643820081. The next prime is 643820083. The reversal of 643820082 is 280028346.

It is an interprime number because it is at equal distance from previous prime (643820081) and next prime (643820083).

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

643820082 is an admirable number.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (643820081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53651668 + ... + 53651679.

It is an arithmetic number, because the mean of its divisors is an integer number (160955022).

Almost surely, 2^643820082 is an apocalyptic number.

643820082 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

643820082 is a wasteful number, since it uses less digits than its factorization.

643820082 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107303352.

The product of its (nonzero) digits is 18432, while the sum is 33.

The square root of 643820082 is about 25373.6099520742. The cubic root of 643820082 is about 863.4850835979.

The spelling of 643820082 in words is "six hundred forty-three million, eight hundred twenty thousand, eighty-two".