643606003 has 2 divisors, whose sum is σ = 643606004. Its totient is φ = 643606002.

The previous prime is 643605979. The next prime is 643606021. The reversal of 643606003 is 300606346.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 643606003 - 2⁵ = 643605971 is a prime.

It is not a weakly prime, because it can be changed into another prime (643606603) 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 as a sum of consecutive naturals, namely, 321803001 + 321803002.

It is an arithmetic number, because the mean of its divisors is an integer number (321803002).

Almost surely, 2^643606003 is an apocalyptic number.

643606003 is a deficient number, since it is larger than the sum of its proper divisors (1).

643606003 is an equidigital number, since it uses as much as digits as its factorization.

643606003 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 28.

The square root of 643606003 is about 25369.3910648246. The cubic root of 643606003 is about 863.3893661136.

The spelling of 643606003 in words is "six hundred forty-three million, six hundred six thousand, three".