643800213 has 24 divisors (see below), whose sum is σ = 1077347648. Its totient is φ = 362843712.

The previous prime is 643800173. The next prime is 643800229. The reversal of 643800213 is 312008346.

It is a happy number.

643800213 is a `hidden beast` number, since 643 + 8 + 0 + 0 + 2 + 13 = 666.

It is not a de Polignac number, because 643800213 - 2⁹ = 643799701 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 (643800233) 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 23 ways as a sum of consecutive naturals, for example, 65395 + ... + 74592.

Almost surely, 2^643800213 is an apocalyptic number.

643800213 is a gapful number since it is divisible by the number (63) formed by its first and last digit.

It is an amenable number.

643800213 is a deficient number, since it is larger than the sum of its proper divisors (433547435).

643800213 is a wasteful number, since it uses less digits than its factorization.

643800213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140073 (or 140070 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 643800213 is about 25373.2184202162. The cubic root of 643800213 is about 863.4762008049.

Adding to 643800213 its reverse (312008346), we get a palindrome (955808559).

The spelling of 643800213 in words is "six hundred forty-three million, eight hundred thousand, two hundred thirteen".