643303 has 2 divisors, whose sum is σ = 643304. Its totient is φ = 643302.

The previous prime is 643301. The next prime is 643369. The reversal of 643303 is 303346.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 643303 - 2¹ = 643301 is a prime.

Together with 643301, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643301) by changing a digit.

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 as a sum of consecutive naturals, namely, 321651 + 321652.

It is an arithmetic number, because the mean of its divisors is an integer number (321652).

2⁶⁴³³⁰³ is an apocalyptic number.

643303 is a deficient number, since it is larger than the sum of its proper divisors (1).

643303 is an equidigital number, since it uses as much as digits as its factorization.

643303 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 19.

The square root of 643303 is about 802.0617183235. The cubic root of 643303 is about 86.3253853273.

Adding to 643303 its reverse (303346), we get a palindrome (946649).

It can be divided in two parts, 643 and 303, that added together give a triangular number (946 = T₄₃).

The spelling of 643303 in words is "six hundred forty-three thousand, three hundred three".