643764883 has 2 divisors, whose sum is σ = 643764884. Its totient is φ = 643764882.

The previous prime is 643764851. The next prime is 643764889. The reversal of 643764883 is 388467346.

643764883 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 643764883 - 2⁵ = 643764851 is a prime.

It is not a weakly prime, because it can be changed into another prime (643764889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321882441 + 321882442.

It is an arithmetic number, because the mean of its divisors is an integer number (321882442).

Almost surely, 2^643764883 is an apocalyptic number.

643764883 is a deficient number, since it is larger than the sum of its proper divisors (1).

643764883 is an equidigital number, since it uses as much as digits as its factorization.

643764883 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2322432, while the sum is 49.

The square root of 643764883 is about 25372.5222041483. The cubic root of 643764883 is about 863.4604054429.

The spelling of 643764883 in words is "six hundred forty-three million, seven hundred sixty-four thousand, eight hundred eighty-three".