643303233 has 6 divisors (see below), whose sum is σ = 929215794. Its totient is φ = 428868816.

The previous prime is 643303223. The next prime is 643303249. The reversal of 643303233 is 332303346.

643303233 is a `hidden beast` number, since 6 + 4 + 330 + 323 + 3 = 666.

It can be written as a sum of positive squares in only one way, i.e., 524776464 + 118526769 = 22908^2 + 10887^2 .

It is not a de Polignac number, because 643303233 - 2⁴ = 643303217 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 643303197 and 643303206.

It is not an unprimeable number, because it can be changed into a prime (643303223) 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 in 5 ways as a sum of consecutive naturals, for example, 35739060 + ... + 35739077.

It is an arithmetic number, because the mean of its divisors is an integer number (154869299).

Almost surely, 2^643303233 is an apocalyptic number.

It is an amenable number.

643303233 is a deficient number, since it is larger than the sum of its proper divisors (285912561).

643303233 is a wasteful number, since it uses less digits than its factorization.

643303233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71478143 (or 71478140 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 27.

The square root of 643303233 is about 25363.4231325348. The cubic root of 643303233 is about 863.2539574945.

Adding to 643303233 its reverse (332303346), we get a palindrome (975606579).

The spelling of 643303233 in words is "six hundred forty-three million, three hundred three thousand, two hundred thirty-three".