643488133 has 4 divisors (see below), whose sum is σ = 644075820. Its totient is φ = 642900448.

The previous prime is 643488119. The next prime is 643488187. The reversal of 643488133 is 331884346.

643488133 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 331884346 = 2 ⋅165942173.

It can be written as a sum of positive squares in 2 ways, for example, as 55086084 + 588402049 = 7422^2 + 24257^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643488133 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 (643488103) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 292198 + ... + 294391.

It is an arithmetic number, because the mean of its divisors is an integer number (161018955).

Almost surely, 2^643488133 is an apocalyptic number.

It is an amenable number.

643488133 is a deficient number, since it is larger than the sum of its proper divisors (587687).

643488133 is a wasteful number, since it uses less digits than its factorization.

643488133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 587686.

The product of its digits is 165888, while the sum is 40.

The square root of 643488133 is about 25367.0678833798. The cubic root of 643488133 is about 863.3366558543.

The spelling of 643488133 in words is "six hundred forty-three million, four hundred eighty-eight thousand, one hundred thirty-three".